An alloy steel/alumina composite was successfully fabricated by pressureless infiltration of X10CrNi18-8 steel melt on 30% (mass fraction) Ni-containing alumina based composite ceramic (Ni/Al₂O₃) at 1 600 °C. The infiltration quality and interfacial bonding behavior were investigated by SEM, EDS, XRD and tensile tests. The results show that there is an obvious interfacial reaction layer between the alloying steel and the Ni/Al₂O₃ composite ceramic. The interfacial reactive products are (Fe_xAl_y)₃O₄ intermetallic phase and (Al_xCr_y)₂O₃ solid solution. The interfacial bonding strength is as high as about 67.5 MPa. The bonding mechanism of X10CrNi18-8 steel with the composite ceramic is that Ni inside the ceramic bodies dissolves into the alloy melt and transforms into liquid channels, consequently inducing the steel melt infiltrating and filling in the pores and the liquid channels. Moreover, the metallurgical bonding and interfacial reactive bonding also play a key role on the stability of the bonding interface.

Aiming at developing novel microwave-transparent ceramics with low dielectric loss, high thermal conductivity and high strength, Si₃N₄-AlN (30%, mass fraction) composite ceramics with La₂O₃ as sintering additive were prepared by hot-pressing at 1 800 °C and subsequently annealed at 1 450 °C and 1 850 °C for 2 h and 4 h, respectively. The materials were characterized by XRD and SEM. The effect of annealing process on the phase composition, sintering performance, microstructure, bending strength, dielectric loss and thermal conductivity of the materials was investigated. The results showed that both annealing at 1 850 °C and 1 450 °C promoted the phase transformation of α-Si₃N₄ to β-Si₃N₄. After annealing at 1 850 °C, grain growth to a certain extent occurred in the materials. Especially, the elongated β-Si₃N₄ grains showed a slight increase in diameter from 0.2 μm to 0.6 μm approximately and a decrease in aspect ratio. As a result, as the annealing time increased to 4 h, the bending strength declined from 456 MPa to 390 MPa, whereas the dielectric loss decreased to 2.15×10⁻³ and the thermal conductivity increased to 16.3 W/(m·K) gradually. When annealed at 1 450 °C, increasing the annealing time to 4 h significantly promoted the crystallization of glassy phase to La₂Si₆N₈O₃ phase in the materials, which led to the increase in bending strength to 619 MPa and thermal conductivity to 15.9 W/(m·K), respectively, and simultaneously the decrease in dielectric loss to 1.53×10⁻³.

A novel Ti-based Ti-Mn composite anode used for electrolytic manganese dioxide (EMD) fabrication was developed by a two-step heating manganizing technique. The effects of sintering temperature on the manganized microstructure and the performance of the composite anode were studied by scanning electron microscopy (SEM), mechanical properties tests at room temperature and electrochemical methods. The results show that the thickness of the diffusion layer increases with the increase of sintering temperature up to 1 100 °C; whereas, the surface Mn content increases and reaches the maximum at 1 000 °C and then decreases thereafter. Lower surface Mn content is beneficial for the enhanced corrosion resistance and lowered open cell voltage in electrolytic process. The new anode prepared under the optimized conditions has been applied in industry and exhibits superior economic benefits to conventional Ti anodic materials.

A series of carbonaceous mesophase spherule/activated carbon composites were prepared as anode materials for super lithium ion capacitors using carbonaceous mesophase spherules as the core materials and pitch as the active carbon shell precursor. The structures of the composites were examined by scanning electron microscopy and X-ray diffractometry. The electrochemical performance was investigated in electric double layer capacitor and half-cell. The results show that, the composite exhibits good performance in both capacitor and battery with a high reversible capacity of 306.6 mA·h/g (0.2C) in the half-cell, along with a capacitance of 25.8 F/g in the capacitor when an optimum ratio of carbonaceous mesophase spherules to active carbon is adopted. The composite also shows a favorable rate performance and good cycle ability. A working model of this anode in super lithium ion capacitors was established.

A LiFePO₄/(C+Fe₂P) composite cathode material was prepared by a sol-gel method using Fe(NO₃)₃·9H₂O, LiAc·H₂O, NH₄H₂PO₄ and citric acid as raw materials, and the physical properties and electrochemical performance of the composite cathode material were investigated by X-ray diffractometry (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electrochemical tests. The Fe₂P content, morphology and electrochemical performance of LiFePO₄/(C+Fe₂P) composite depend on the calcination temperature. The optimized LiFePO₄/(C+Fe₂P) composite is prepared at 650 °C and the optimized composite exhibits sphere-like morphology with porous structure and Fe₂P content of about 3.2% (mass fraction). The discharge capacity of the optimized LiFePO₄/(C+Fe₂P) at 0.1C is 156 and 161 mA·h/g at 25 and 55 °C, respectively, and the corresponding capacity retentions are 96% after 30 cycles; while the capacity at 1C is 142 and 149 mA·h/g at 25 and 55 °C, respectively, and the capacity still remains 135 and 142 mA·h/g after 30 cycles at 25 and 55 °C, respectively.

A partial substitution of Ni by Mn was implemented in order to improve the hydriding and dehydriding kinetics of the Mg₂Ni-type alloys. The nanocrystalline and amorphous Mg₂Ni-type Mg₂Ni_1−xMn_x (x=0, 0.1, 0.2, 0.3, 0.4) alloys were synthesized by the melt-spinning technique. The structures of the as-cast and spun alloys were studied by X-ray diffractometry (XRD), scanning electron microscopy (SEM) and high resolution transmission electron microscopy (HRTEM). The hydrogen absorption and desorption kinetics of the alloys were measured with an automatically controlled Sieverts apparatus. The results show that the as-spun Mn-free alloy holds a typical nanocrystalline structure, whereas the as-spun alloys containing Mn display a nanocrystalline and amorphous structure, confirming that the substitution of Mn for Ni intensifies the glass forming ability of the Mg₂Ni-type alloy. The hydrogen absorption and desorption capacities and kinetics of the alloys increase with increasing the spinning rate, for which the nanocrystalline and amorphous structure produced by the melt spinning is mainly responsible. The substitution of Mn for Ni evidently improves the hydrogen desorption performance. The hydrogen desorption capacities of the as-cast and spun alloys rise with the increase in the percentage of Mn substitution.

Microsized single-crystalline Co₃O₄ has been synthesized by high-temperature hydrolysis of CoCl₂·2H₂O at 600 °C. The samples were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results reveal that the as-prepared powders are microsized single-crystalline Co₃O₄ with cubic spinel structure. An increase in the high-temperature hydrolysis time results in the evolution of particle shapes from cube to quasi-sphere, and then to octahedron. The effect of NaCl additive on the surface morphologies of Co₃O₄ particles was experimentally investigated. The results indicate that the NaCl additive acts as an inert disperse phase in the high-temperature hydrolysis, and prevents the aggregation of Co₃O₄ particles effectively.

The electronic structure and optical properties of the tetragonal phase quaternary arsenide oxides YZnAsO and LaZnAsO were studied using density-functional theory (DFT) within generalized gradient approximation (GGA). The band structure along the higher symmetry axes in the Brillouin zone, the density of states (DOS) and the partial density of states (PDOS) were presented. The calculated energy band structures show that both YZnAsO and LaZnAsO are indirect gap semiconductors with band gap of 1.173 1 eV and 1.166 5 eV, respectively. The DOS and PDOS show the hybridization of Y-O/La-O atom orbits and Zn-As atom orbits. The dielectric function, reflectivity, absorption coefficient, refractive index, electron energy-loss function and optical conductivity were presented in an energy range from 0 to 25 eV for discussing the optical properties of YZnAsO and LaZnAsO.

A highly ordered porous alumina template with pores of 45 nm in diameter was synthesized by a two-step electrochemical anodizing process. The influence of pore-enlargement treatment on the porous structure and tribological properties of the film was investigated, and ultrasonic impregnation technology was applied on it to form self-lubricating surface. The structure of the self-lubricating film and its tribological properties were investigated in detail. It can be concluded that the optimum time of pore-enlargement treatment is 20 min. The diameter of the pores and the surface porosity of the film are about 70 nm and 30%, respectively, while the film maintains the property of its high hardness. Under the same friction condition, the frictional coefficient of the self-lubricating film is 0.18, much lower than that of the anodic aluminum oxide template, which is 0.52. In comparison with the lubricating surface of non-porous dense anodic aluminum oxide template, the lubricating surface fabricated by the ultrasonic impregnation method on the porous anodic aluminum oxide template keeps longer period with low friction coefficient. SEM examination shows that some C₆₀ particles have been embedded in the nanoholes of the anodic aluminum oxide template by the ultrasonic impregnation technology.

A novel grain boundary (GB) model characterized with different angles and positions in the nanowire was set up. By means of device simulator, the effects of grain boundary angle and location on the electrical performance of ZnO nanowire FET (Nanowire Field-Effect Transistor) with a wrap-around gate configuration, were explored. With the increase of the grain boundary angle, the electrical performance degrades gradually. When a grain boundary with a smaller angle, such as 5° GB, is located close to the source or drain electrode, the grain boundary is partially depleted by an electric field peak, which leads to the decrease of electron concentration and the degradation of transistor characteristics. When the 90° GB is located at the center of the nanowire, the action of the electric field is balanced out, so the electrical performance of transistor is better than that of the 90° GB located at the other positions.

An aluminum/copper clad composite was fabricated by the casting-cold extrusion forming technology and the microstructures of the products were observed and analyzed. It is found that aluminum grains at the interface are refined in the radial profiles of cone-shaped deformation zone, but the grains in the center maintain the original state and the grain size is non-uniform. A clear boundary presents between the refined area and center area. In contrast, the copper grains in the radial profiles have been significantly refined. In the center area of the copper, the grains are bigger than those at the boundary. On the surface of the deformable body, the grain size is the smallest, but with irregular grain morphology. After the product is entirely extruded, all the copper and aluminum grains are refined with small and uniform morphology. In the center area, the average diameter of aluminum grains is smaller than 5 μm, and the copper grain on the surface is about 10 μm. At the interface, the grain size is very small, with a good combination of copper and aluminum. The thickness of interface is in the range of 10–15 μm. Energy spectrum analysis shows that CuAl₃ phase presents at the interface.

The distribution of shear stress on the cross-section of plastic metal solid circular shaft under pure torsion yielding, the applicability of complete plastic model assumption and the shear stress formula were researched. Based on the shear stress formula of circular shaft under pure torsion in elastic stage, the formula of torque in elastic stage and the definition of yield, it is obtained that the yielding stage of plastic metal shaft under pure torsion is only a surface phenomenon of torque-torsion angle relationship, and the distribution of shear stress is essentially different from that of tensile stress when yielding under uniaxial tension. The pure torsion platform-torsion angle and the shape of torque-torsion angle curve cannot change the distribution of shear stress on the shaft cross-section. The distribution of shear stress is still linear with the maximum shear stress τ_s. The complete plasticity model assumption is not in accordance with the actual situation of shaft under torsion. The experimental strength data of nine plastic metals are consistent with the calculated results of the new limiting strain energy strength theory (LSEST). The traditional yield stress formula for plastic shaft under torsion is reasonable. The shear stress formula based on the plane assumption in material mechanics is applicable for all loaded stages of torsion shaft.

To perform the mechanism study of special association for vancomycin and D-Ala-D-Ala-containing peptides on the interface of solution and self-assemble monolayer, the binding between vancomycin and pentapeptide (Lys-Lys-Gly-D-Ala-D-Ala) was investigated by flow injection surface plasmon resonance (FI-SPR) and flow injection quartz crystal microbalance (FI-QCM). To facilitate the formation of a compact vancomycin adsorbates layer with a uniform surface orientation, vancomycin molecules were attached onto a preformed alkanethiol self-assembled monolayer. By optimizing the conditions for the binding between Lys-Lys-Gly-D-Ala-D-Ala and vancomycin on the assembled chip, the detecting limit of Lys-Lys-Gly-D-Ala-D-Ala was greatly improved (reaching 0.5×10⁻⁶ mol/L or 7.5×10⁻¹² mol). The equilibrium constant of the association of Lys-Lys-Gly-D-Ala-D-Ala with vancomycin was also obtained (K_Ads=5.0×10⁴ L/mol).

Based on the starch hydrolysis reaction accelerated by microwave irradiation with α-amylase, the circular dichroism (CD) and secondary structure changes of α-amylase under the condition of microwave irradiation and water bath were studied by circular dichroism spectra. The results showed that, both the peak heights (at λ=193 nm) of the CD spectra of the samples treated by microwave irradiation and water bath reduced. The reduced rate by microwave irradiation ranged from 140% to 220%, while the reduced rate by water bath ranged from 60% to 140%. The peak of the sample treated by microwave irradiation for 60 min disappeared at λ=193 nm, while the sample showed a wake peak by water bath. The peak position by microwave irradiation emerged a blue shift in the range of 5–8 nm at λ=204 nm and λ=220 nm, while it emerged in the range of 3–5 nm by water bath. With time going on, the microwave irradiation and water bath have prompted the secondary structure of α-helix, β-sheet, β-turn and the mutual transformations of random coil, but the trends were different.

In order to achieve a more efficient way to accurately detect the position of the fire source of spontaneous combustion underground mine, a simple fire source locating method, based on infrared scanning system which can determine the point where the highest temperature on the surface of igniting ores occurs, was proposed. First, the differential equations that describe heat flow in ore body were presented and the relationship between the surface temperature distribution and the depth and intensity of inner fire source was established with a relatively simple heat transfer model. With the solution of equation, the expression of the relationship between the surface temperature distribution and the inner fire source was deduced and the mathematical-physical model of heat transfer process was set up. Then, with the model, visualization of fire source on the basis of MATLAB simulation platform was realized. The results show that: 1) within 10 m, when the detecting depth is less than 2 m, the temperature perturbation on ores surface can change rapidly, and then slowly; after 4 m, in contrast, it changes very little, and is even close to zero at 10 m; 2) When it is close to self-ignition duration and the detective depths are 2, 5 and 10 m, respectively, the maximum temperature differences are correspondingly 0.5, 0.04 and 0.005 °C in the scope of 1 m×1 m; under the same condition, the maximum temperature differences are 1.391, 0.136 and 0.018 °C, respectively, in the scope of 2 m×2 m. Therefore, this system can be used to measure the temperature differences on the surface of ore body and determine the highest temperature point directly. Also, it is possible to determine the depth of fire source and its intensity by locating method of fire source indirectly.

The structure characteristics and adhesive property of humic substance (HS) extracted with different methods were mainly studied by terms of elementary analysis, visible spectrum, FT-IR spectroscopy, viscosity, adsorption and pelletizing experiments. The results show that HSs extracted with new method (HS-a) own higher degree of aromatization and polymerization, larger relative molecular mass and more polar functional groups than HS extracted with usual method (HS-b). The viscosity of HS-b is about 30–40 mPa·s lower than that of HS-a. The maximum adsorption amounts of HS-a and HS-b onto iron concentrates are 9.11 mg/g and 8.08 mg/g, respectively. Meanwhile, HS-a has a better performance than HS-b in the practical application for pelletizing of iron concentrates. The difference in agglomeration behaviors with iron concentrates lies in the differences of the structure characteristics of HSs. With higher content of polar functional groups, larger relative molecular mass and viscosity of HSs, the agglomeration behavior is improved.

To improve antagonistic metabolites production of Bacillus subtilis strain BS501a, physical parameters of fermentation and metal inorganic salts in medium, namely initial pH value, culture temperature, fermentation time, concentrations of CaCl₂, FeSO₄, ZnSO₄, MnSO₄ and MgSO₄, were optimized using one-factor-at-a-time and orthogonal tests. The results show that the optimal physical parameters of fermentation are an initial pH of 7.0, a culture temperature of 30 °C, and a fermentation time of 48 h. The optimal concentrations of metal inorganic salts in basal medium are 10.2 mmol/L CaCl₂, 0.4 mmol/L FeSO₄, 3.5 mmol/L ZnSO₄, 0.6 mmol/L MnSO₄ and 2.0 mmol/L MgSO₄. Among the metal inorganic salts, MgSO₄ and MnSO₄ play important roles in the improvement of the antagonistic metabolites production of B. subtilis strain BS501a; especially, MgSO₄ contributes a highly significant effect. The average diameter of inhibition zone of the BS501a filtered fermentation supernatant (FFS) cultured in the optimal fermentation conditions against Magnaporthe grisea DWBJ329 reaches 71.4 mm, and there is 2.4-fold increase in antifungal activity as compared with 21.2 mm under the pre-optimized conditions.

A total of 126 bacterial strains were isolated from soil samples. Among them, 11 isolates were found positive for amylase production. Strain YL produced the largest zone of clearance on plate assay. The isolate YL was identified as Bacillus sp. based on morphological and physiochemical characterization. According to 16S rRNA gene sequencing data, the closest phylogenetic neighbor of strain YL was Bacillus amyloliquefaciens (99.54%). After that, an optimization of culture conditions was carried out for the improvement of α-amylase production. Response surface methodology (RSM) was applied to evaluate the effect of medium components including wheat bran, cottonseed extract, yeast extract, starch, NaCl and CaCl₂. Three variables (wheat bran, cottonseed extract, and starch), which were identified to significantly affect amylase production by Plackett-Burman design were further optimized using response surface methodology of Box-Behnken design (BBD). The optimal concentrations estimated for each variable related to the maximum of amylase activity (86 kU/mL) were 10.80 g/L wheat bran, 9.90 g/L cottonseed extract, 0.5 g/L starch, 2.0 g/L yeast extract, 5.00 g/L NaCl and 2.00 g/L CaCl₂. The fermentation using optimized culture medium allowed a significant increase in amylase production (by 3-fold). The improvement in the α-amylase production after optimization process can be considered adequate for large-scale applications.

To investigate the hydrogen permeability of calcium fluoride used for electroslag remelting (ESR) process, “Gas-slag-metal” osmosis process under argon atmosphere saturated with water vapor at 318 K was used to study the hydrogen permeability of slag containing calcium fluoride. The results indicate that the conventional slag, consisting of 70% CaF₂ and 30% Al₂O₃, has the lowest hydrogen permeability. A parameter E_H was proposed for evaluation of the hydrogen permeability of slags containing calcium fluoride. The hydrogen permeability decreases with increasing E_H to a certain extent. An appropriate choice of slag for the ESR process can be obtained. These results also suggest that the hydrogen pick-up in steel after remelting might be reduced when a slag with low hydrogen permeability is used.

Factors on degradation of chlorothalonil (CLT) in water by high frequency ultrasonic irradiation were investigated. The effects of initial concentration of chlorothalonil, dosages of tertiary butyl alcohol, humic acid and initial pH value on degradation of chlorothalonil, as well as the reaction mechanism were studied. The results reveal that chlorothalonil could be effectively degradated by ultrasonic irradiation. The reaction constant value k_app decreased from 0.014 1 to 0.010 2 min⁻¹ with the initial concentration increasing from 50 to 400 μg/L during 180 min irradiation. Tertiary butyl alcohol had negative effect on chlorothalonil degradation, while lower concentration of humic acid promoted the sonolysis, and k_app declined with the further concentration increasing. The k_app varied little when the pH value ranged from 3.10 to 10.28. It may be concluded that mechanical and pyrolysis process played main roles on the degradation of chlorothalonil in ultrasonic irradiation rather than ·OH attack. The electrical energy per order (E_Eo) values for sonolysis degradation of CLT were also calculated to evaluate the cost of the process.

A hydrometallurgical process for indium extraction and ferric oxide powder preparation for soft magnetic ferrite material was developed. Using reduction lixivium from high-acid reductive leaching of zinc oxide calcine as raw solution, copper and indium were firstly recovered by iron powder cementation and neutralization. The recovery ratios of Cu and In are 99% and 95%, respectively. Some harmful impurities that have negative influences on magnetic properties of soft magnetic ferrite material are deeply removed with sulfidization purification and neutral flocculation method. Under the optimum conditions, the content of impurities like Cu, Pb, As, Al in pure Zn-Fe sulfate solution are less than 0.004 g/L, but those of Cd, Si, Ca and Mg are relatively high. Finally, thermal precipitation of iron is carried out at 210 °C for 1.5 h. The precipitation ratio of Fe is 93.33%. Compared with the quality standard of ferric oxide for soft magnetic ferrite materials, the contents of Al and Mg in obtained ferric oxide powder meet the requirement of YHT1 level of ferric oxide, and those of Si, Ca meet the requirement of YHT3 level of ferric oxide. XRD and SEM characterizations confirm that the obtained sample is well-dispersed spindle spherule with regular α-Fe₂O₃ crystal structure. The length-to-diameter ratio of α-Fe₂O₃ powder is (3–4):1 with an average particle size of 0.5 μm.

A novel iterative technique, the phase descent search (PDS) algorithm, for M-ary phase shift keying (M-PSK) symbols detection was proposed. This technique constrained the solution to have a unit magnitude and it was based on coordinate descent iterations where coordinates were the unknown symbol phases. The PDS algorithm, together with a descent local search (also implemented as a version of the PDS algorithm), was used multiple times with different initializations in a proposed multiple phase detector; the solution with the minimum cost was then chosen as the final solution. The simulation results show that for highly loaded multiuser scenarios, the proposed technique has a detection performance that is close to the single-user bound. The results also show that the multiple phase detector allows detection in highly overloaded scenarios and it exhibits near-far resistance. In particular, the detector has a performance that is significantly better, and complexity that is significantly lower, than that of the detector based on semi-definite relaxation.

To overcome the influence of on-orbit extreme temperature environment on the tool pose (position and orientation) accuracy of a space robot, a new self-calibration method based on a measurement camera (hand-eye vision) attached to its end-effector was presented. Using the relative pose errors between the two adjacent calibration positions of the space robot, the cost function of the calibration was built, which was different from the conventional calibration method. The particle swarm optimization algorithm (PSO) was used to optimize the function to realize the geometrical parameter identification of the space robot. The above calibration method was carried out through self-calibration simulation of a six-DOF space robot whose end-effector was equipped with hand-eye vision. The results showed that after calibration there was a significant improvement of tool pose accuracy in a set of independent reference positions, which verified the feasibility of the method. At the same time, because it was unnecessary for this method to know the transformation matrix from the robot base to the calibration plate, it reduced the complexity of calibration model and shortened the error propagation chain, which benefited to improve the calibration accuracy.

To improve motion graph based motion synthesis, semantic control was introduced. Hybrid motion features including both numerical and user-defined semantic relational features were extracted to encode the characteristic aspects contained in the character’s poses of the given motion sequences. Motion templates were then automatically derived from the training motions for capturing the spatio-temporal characteristics of an entire given class of semantically related motions. The data streams of motion documents were automatically annotated with semantic motion class labels by matching their respective motion class templates. Finally, the semantic control was introduced into motion graph based human motion synthesis. Experiments of motion synthesis demonstrate the effectiveness of the approach which enables users higher level of semantically intuitive control and high quality in human motion synthesis from motion capture database.

Based on flexible pneumatic actuator (FPA), bending joint and side-sway joint, a new kind of pneumatic dexterous robot finger was developed. The finger is equipped with one five-component force sensor and four contactless magnetic rotary encoders. Mechanical parts and FPAs are integrated, which reduces the overall size of the finger. Driven by FPA directly, the joint output torque is more accurate and the friction and vibration can be effectively reduced. An improved adaptive genetic algorithm (IAGA) was adopted to solve the inverse kinematics problem of the redundant finger. The statics of the finger was analyzed and the relation between fingertip force and joint torque was built. Finally, the finger force/position control principle was introduced. Tracking experiments of fingertip force/position were carried out. The experimental results show that the fingertip position tracking error is within ±1 mm and the fingertip force tracking error is within ±0.4 N. It is also concluded from the theoretical and experimental results that the finger can be controlled and it has a good application prospect.

The influences of the mask wall angle on the current density distribution, shape of the evolving cavity and machining accuracy were investigated in electrochemical machining (ECM) by mask. A mathematical model was developed to predict the shape evolution during the ECM by mask. The current density distribution is sensitive to mask wall angle. The evolution of cavity is determined by the current density distribution of evolving workpiece surface. The maximum depth is away from the center of holes machined, which leads to the island appearing at the center of cavity for mask wall angles greater than or equal to 90° (β≥90°). The experimental system was established and the simulation results were experimentally verified. The results indicate that the simulation results of cavity shape are consistent with the actual ones. The experiments also show that the repetition accuracy of matrix-hole for β≥90° is higher than that for β<90°. A hole taper is diminished, and the machining accuracy is improved with the mask wall angle increasing.

To enhance the speech quality that is degraded by environmental noise, an algorithm was proposed to reduce the noise and reinforce the speech. The minima controlled recursive averaging (MCRA) algorithm was used to estimate the noise spectrum and the partial masking effect which is one of the psychoacoustic properties was introduced to reinforce speech. The performance evaluation was performed by comparing the PESQ (perceptual evaluation of speech quality) and segSNR (segmental signal to noise ratio) by the proposed algorithm with the conventional algorithm. As a result, average PESQ by the proposed algorithm was higher than the average PESQ by the conventional noise reduction algorithm and segSNR was higher as much as 3.2 dB in average than that of the noise reduction algorithm.

A method used to detect anomaly and estimate the state of vehicle in driving was proposed. The kinematics model of the vehicle was constructed and nonholonomic constraint conditions were added, which refer to that once the vehicle encounters the faults that could not be controlled, the constraint conditions are violated. Estimation equations of the velocity errors of the vehicle were given out to estimate the velocity errors of side and forward. So the stability of the whole vehicle could be judged by the velocity errors of the vehicle. Conclusions were validated through the vehicle experiment. This method is based on GPS/INS integrated navigation system, and can provide foundation for fault detections in unmanned autonomous vehicles.

In order to provide some theoretical guideline for the structure design of the new type externally pressurized spherical air bearings, the static characteristics and the factors affecting the static characteristics of the air bearings were analyzed. A finite volume method was adopted to discretize the three-dimensional steady-state compressible Navier-Stokes equations, and a modified SIMPLE algorithm for compressible fluid was applied to solve the discretized governing equations. The pressure field and velocity field of the air bearings were obtained, and the factors and rules affecting the static characteristics were analyzed. The results show that the pressure of near air intakes can reach above 80% of air supply pressure, and there is a pressure steep fall around the air intakes. When the film thickness is greater than 20 μm, the bearing capacity rapidly decreases as film thickness increases. As the air supply pressure increases from 0.2 to 0.6 MPa, the maximum static stiffness increases by more than three times. The calculation method proposed well fits the general principle, which can be extended to the characteristic analysis of other air bearings.

In order to present basic guidance for system calibration of split Hopkinson pressure bar (SHPB) with the special shape striker, wave characteristics and dynamic responses of SHPB under striker impact were analyzed. Stress generated by the special shape striker tends to have a half-sine waveform and has little wave dispersion during its propagation. Impact velocities of the special shape striker and peak values of generated stress still have linear relation but with a different coefficient from that of cylindrical strikers. From stress histories on the surfaces of the input bar impacted by the special shape striker off-axially and obliquely, it is found that the misalignment impacts usually trigger wave distortion and amplitude decrease, which can be used to identify the poor system adjustment. Finally, the system calibration of SHPB with the special shape striker can be classified into four steps: system adjustment, wave distortion identification, measurement calibration and transmission calibration, where the measurement calibration factor and transmission calibration factor are elaborated and redefined.

Most existing work on survivability in mobile ad-hoc networks (MANETs) focuses on two dimensional (2D) networks. However, many real applications run in three dimensional (3D) networks, e.g., climate and ocean monitoring, and air defense systems. The impact on network survivability due to node behaviors was presented, and a quantitative analysis method on survivability was developed in 3D MANETs by modeling node behaviors and analyzing 3D network connectivity. Node behaviors were modeled by using a semi-Markov process. The node minimum degree of 3D MANETs was discussed. An effective approach to derive the survivability of k-connected networks was proposed through analyzing the connectivity of 3D MANETs caused by node misbehaviors, based on the model of node isolation. The quantitative analysis of node misbehaviors on the survivability in 3D MANETs is obtained through mathematical description, and the effectiveness and rationality of the proposed approach are verified through numerical analysis. The analytical results show that the effect from black and gray attack on network survivability is much severer than other misbehaviors.

To overcome the deficiencies addressed in the conventional PID control and improve the dynamic performance and robustness of the system, a simple design and parameters tuning approach of internal model control-PID (IMC-PID) controller was proposed for the first order plus time-delay (FOPTD) process and the second order plus time-delay (SOPTD) process. By approximating the time-delay term of the process model with the first-order Taylor series, the expressions for IMC-PID controller parameters were derived, and they had only one adjustable parameter λ which was directly related to the dynamic performance and robustness of the system. Moreover, an analytical approach of selecting λ was given based on the maximum sensitivity M_s. Then, the robust tuning of the system could be achieved according to the value of M_s. In addition, the proposed method could be extended to the integrator plus time-delay (IPTD) process and the first order delay integrating (FODI) process. Simulation studies were carried out on various processes with time-delay, and the results show that the proposed method could provide a better dynamic performance of both the set-point tracking and disturbance rejection and robustness against parameters perturbation.

Consensus problems for discrete-time multi-agent systems were focused on. In order to design effective consensus protocols, which were aimed at ensuring that the concerned states of agents converged to a common value, a new consensus protocol for general discrete-time multi-agent system was proposed based on Lyapunov stability theory. For discrete-time multi-agent systems with desired trajectory, trajectory tracking and formation control problems were studied. The main idea of trajectory tracking problems was to design trajectory controller such that each agent tracked desired trajectory. For a type of formation problem with fixed formation structure, the formation structure set was introduced. According to the formation structure set, each agent can track its individual desired trajectory. Finally, simulations were provided to demonstrate the effectiveness of the theoretical results. The numerical results show that the states of agents converge to zero with consensus protocol, which is said to achieve a consensus asymptotically. In addition, through designing appropriate trajectory controllers, the simulation results show that agents converge to the desired trajectory asymptotically and can form different formations.

A novel layered method was proposed to solve the problem of Web services composition. In this method, services composition problem was formally transformed into the optimal matching problem of every layer, then optimal matching problem was modeled based on the hypergraph theory, and solved by computing the minimal transversals of the hypergraph. Meanwhile, two optimization algorithms were designed to discard some useless states at the intermediary steps of the composition algorithm. The effectiveness of the composition method was tested by a set of experiments, in addition, an example regarding the travel services composition was also given. The experimental results show that this method not only can automatically generate composition tree whose leaf nodes correspond to services composition solutions, but also has better performance on execution time and solution quality by adopting two proposed optimization algorithms.

Consensus tracking control problems for single-integrator dynamics of multi-agent systems with switching topology are investigated. In order to design effective consensus tracking protocols for a more general class of networks, which are aimed at ensuring that the concerned states of agents converge to a constant or time-varying reference state, new consensus tracking protocols with a constant and time-varying reference state are proposed, respectively. Particularly, by contrast with spanning tree, an improved condition of switching interaction topology is presented. And then, convergence analysis of two consensus tracking protocols is provided by Lyapunov stability theory. Moreover, consensus tracking protocol with a time-varying reference state is extended to achieve the formation control. By introducing formation structure set, each agent can gain its individual desired trajectory. Finally, several simulations are worked out to illustrate the effectiveness of theoretical results. The test results show that the states of agents can converge to a desired constant or time-varying reference state. In addition, by selecting appropriate structure set, agents can maintain the expected formation under random switching interaction topologies.

Firstly, general regression neural network (GRNN) was used for variable selection of key influencing factors of residential load (RL) forecasting. Secondly, the key influencing factors chosen by GRNN were used as the input and output terminals of urban and rural RL for simulating and learning. In addition, the suitable parameters of final model were obtained through applying the evidence theory to combine the optimization results which were calculated with the PSO method and the Bayes theory. Then, the model of PSO-Bayes least squares support vector machine (PSO-Bayes-LS-SVM) was established. A case study was then provided for the learning and testing. The empirical analysis results show that the mean square errors of urban and rural RL forecast are 0.02% and 0.04%, respectively. At last, taking a specific province RL in China as an example, the forecast results of RL from 2011 to 2015 were obtained.

To adjust the variance of source rate in linear broadcast networks, global encoding kernels should have corresponding dimensions to instruct the decoding process. The algorithm of constructing such global encoding kernels is to adjust heterogeneous network to possible link failures. Linear algebra, graph theory and group theory are applied to construct one series of global encoding kernels which are applicable to all source rates. The effectiveness and existence of such global encoding kernels are proved. Based on information flow, the algorithm of construction is explicitly given within polynomial time O(|E|·|T|·ω_max²), and the memory complexity of algorithm is O(|E|). Both time and memory complexity of this algorithm proposed can be O(ω_max) less than those of algorithms in related works.

A mathematical mechanism model was proposed for the description and analysis of the heat-stirring-acid leaching process. The model is proved to be effective by experiment. Afterwards, the leaching problem was formulated as a constrained multi-objective optimization problem based on the mechanism model. A two-stage guide multi-objective particle swarm optimization (TSG-MOPSO) algorithm was proposed to solve this optimization problem, which can accelerate the convergence and guarantee the diversity of pareto-optimal front set as well. Computational experiment was conducted to compare the solution by the proposed algorithm with SIGMA-MOPSO by solving the model and with the manual solution in practice. The results indicate that the proposed algorithm shows better performance than SIGMA-MOPSO, and can improve the current manual solutions significantly. The improvements of production time and economic benefit compared with manual solutions are 10.5% and 7.3%, respectively.

Short-term forecasting is a difficult problem because of the influence of non-linear factors and irregular events. A novel short-term forecasting method named TIK was proposed, in which ARMA forecasting model was used to consider the load time series trend forecasting, intelligence forecasting DESVR model was applied to estimate the non-linear influence, and knowledge mining methods were applied to correct the errors caused by irregular events. In order to prove the effectiveness of the proposed model, an application of the daily maximum load forecasting was evaluated. The experimental results show that the DESVR model improves the mean absolute percentage error (MAPE) from 2.82% to 2.55%, and the knowledge rules can improve the MAPE from 2.55% to 2.30%. Compared with the single ARMA forecasting method and ARMA combined SVR forecasting method, it can be proved that TIK method gains the best performance in short-term load forecasting.

The alkali-rich rocks, spreading along the suture zone of Jingsha River, refer to the alkali-rich porphyry rocks, which emplace during the Himalaya epoch in northwest of Yunnan Province, and consist of syenit, syenit porphyry, monzonite porphyry and granite porphyry. Petrological chemical analysis results suggest that silica is poor and aluminum is rich, and high potassium large ion lithophile elements (LILE), light rare earth element (LREE) and Sr are obviously detracted in these rocks. High field strength elements (HFSE) and heavy rare earth element (HREE) are depleted, especially Nb, Ta, P and Ti. δ_Eu: 0.09–1.64 shows that plagioclase does not appear fractional crystallization during the formation of alkali-rich rocks. δ³⁴S, H and O isotopes and Pb isotopes suggest that ore-forming fluid is derived from the mantle, and Pb is possibly mixed by mantle, wall rock and crust. The age of Pb in alkali-rich rocks is about 250–220 Ma. The age of alkali porphyry rock (dykes) varies from 30 Ma to 50 Ma. Alkali rocks have strong metallogenetic relation. Au mineralization is associated to the alkali magmatic activities with a relatively high temperature, low pressure and high oxygen fugacity. However, copper mineralization is mainly associated with alkali-sub-alkali magmatic activities in a process of relatively low temperature, high pressure and lower oxygen fugacity.

The dynamic interaction between tunnel lining and its surrounding soil is a complicated issue as the magnitude of seismic wave from bedrock to the structure can be easily influenced by the geometrical layout and structural stiffness of the tunnel. A series of numerical analysis was conducted to study the dynamic response of the tunnel lining of side-by-side and vertically stacked double-tube tunnel since the inertia and kinematic interactions between the tunnel lining and the surrounding soil during an earthquake could induce excessive stresses to the lining itself due to the stiffness variation between the lining and the soil. Real earthquake ground acceleration was used as an input motion in the dynamic analysis. The interactive behavior of bending moment and axial forces, and the displacement of the tunnels were used to evaluate the effect of tunnel geometrical layout on the performance of the lining. It is found that the effect of earthquake on the axial thrust of the lining is insignificant, and there is a reduction of the bending moment in the lining due to the redistribution of the surrounding soil after the earthquake.

In large loop transient electromagnetic method (TEM), the late time apparent resistivity formula cannot truly reflect the geoelectric model, thus it needs to define the all-time apparent resistivity with the position information of measuring point. Utilizing very fast simulated annealing (VFSA) to fit the theoretical electromagnetic force (EMF) and measured EMF could obtain the all-time apparent resistivity of the measuring points in rectangular transmitting loop. The selective cope of initial model of VFSA could be confirmed by taking the late time apparent resistivity of transient electromagnetic method as the prior information. For verifying the correctness, the all-time apparent resistivities of the geoelectric models were calculated by VFSA and dichotomy, respectively. The results indicate that the relative differences of apparent resistivities calculated by these two methods are within 3%. The change of measuring point position has little influence on the tracing pattern of all-time apparent resistivity. The first branch of the curve of all-time apparent resistivity is close to the resistivity of the first layer medium and the last branch is close to the resistivity of the last layer medium, which proves the correctness of the arithmetics proposed.

The theoretical formulations of Coulomb and Rankine still remain as the fundamental approaches to the analysis of most gravity-type retaining wall, with the assumption that sufficient lateral yield will occur to mobilize fully limited conditions behind the wall. The effects of the magnitude of wall movements and different wall-movement modes are not taken into consideration. The disturbance of backfill is considered to be related to the wall movement under translation mode. On the basis of disturbed state concept (DSC), a general disturbance function was proposed which ranged from −1 to 1. The disturbance variables could be determined from the measured wall movements. A novel approach that related to disturbed degree and the mobilized internal frictional angle of the backfill was also derived. A calculation method benefited from Rankine’s theory and the proposed approach was established to predict the magnitude and distribution of earth pressure from the cohesionless backfill under translation mode. The predicted results, including the magnitude and distribution of earth pressure, show good agreement with those of the model test and the finite element method. In addition, the disturbance parameter b was also discussed.

The deformation performance index limits of high reinforced concrete (RC) shear wall components based on Chinese codes were discussed by the nonlinear finite element method. Two typical RC shear wall specimens in the previous work were first used to verify the correctness of the nonlinear finite element method. Then, the nonlinear finite element method was applied to study the deformability of a set of high RC shear wall components designed according to current Chinese codes and with shear span ratio λ≥2.0. Parametric studies were made on the influence of shear span ratio, axial compression ratio, ratio of flexural capacity to shear capacity and main flexural reinforcement ratio of confined boundary members. Finally, the deformation performance index and its limits of high RC shear wall components under severe earthquakes were proposed by the finite element model results, which offers a reference in determining the performance status of RC shear wall components designed based on Chinese codes.

A coupled thermo-hydro-mechanical-migratory model of dual-porosity medium for saturated-unsaturated ubiquitous-joint rockmass was established, in which the stress field and the temperature field were single, but the seepage field and the concentration field were double, and the influences of sets, spaces, angles, continuity ratios, stiffnesses of fractures on the constitutive relationship of the medium were considered. Also, the relative two-dimensional program of finite element method was developed. Taking a hypothetical nuclear waste repository as a calculation example, the case in which the rockmass was unsaturated dual-porosity medium and radioactive nuclide leak was simulated numerically, and the temperatures, negative pore pressures, saturations, flow velocities, nuclide concentrations and principal stresses in the rockmass were investigated. The results show that the negative pore pressures and nuclide concentrations in the porosity and fracture present different changes and distributions. Even though the saturation degree in porosity is only about 1/10 that in fracture, the flow velocity of underground water in fracture is about three times that in porosity because the permeability coefficient of fracture is almost four orders higher than that of porosity. The value of nuclide concentration in fracture is close to that in porosity.

A combined computational and experimental investigation to examine temperature and soot volume fraction in coflow ethylene-air diffusion flames was presented. A numerical simulation was conducted by using a relatively detailed gas-phase chemistry and complex thermal and transport properties coupled with a semi-empirical two-equation soot model. Thermal radiation was calculated using the discrete ordinates method. An image processing technique and a decoupled reconstruction method were used to simultaneously measure the distributions of temperature and soot volume fraction. The results show that the maximum error for temperature does not exceed 10% between the prediction and the measurement. And the maximum error is 6.9% for soot volume fraction between prediction and measurement. Additional simulations were performed to explore the effects of global equivalence ratio on diffusion flames and the soot formation. The results display that the soot formation increases with decreasing the coflow air velocity. And the soot formation in each case appears in the annular region, where the temperature ranges from about 1 000 K to 2 000 K and the profile becomes taller and wider when the coflow air is decreased.

The variation characteristics of aquifer parameters, induced by groundwater source heat pump (GWSHP) operation under variable flow, were theoretically analyzed through a case study, in which the characteristics of building air conditioning load were considered. The results, compared with the constant flow operation, indicate that the influence on the variations of porosity, hydraulic conductivity and confined water head is decreased by 48%, 51% and 71%, respectively, under variable flow operation. The security of variable flow operation is superior to that of constant flow. It is also concluded that the climate region and function of the buildings are primary factors which affect the suitability of variable flow operation in GWSHP.

In order to develop further the application of high temperature heat pipe in hypersonic vehicles thermal protection, the principles and characteristics of high temperature heat pipe used in hypersonic vehicles thermal protection were introduced. The methods of numerical simulation, theory analysis and experiment research were utilized to analyze the frozen start-up and steady state characteristic of the heat pipe as well as the machining improvement for fabricating irregularly shaped heat pipe which is suitable for leading edge of hypersonic vehicles. The results indicate that the frozen start-up time of heat pipe is long (10 min) and there exists large temperature difference along the heat pipe (47 °C/cm), but the heat pipe can reduce the temperature in stagnation area of hypersonic vehicles from 1 926 to 982 °C and work normally during 1 000–1 200°C. How to improve the maximum heat transfer capability and reduce the time needed for start-up from frozen state of the heat pipe by optimizing thermostructure such as designing of a novel wick with high performance is the key point in hypersonic vehicles thermal protection of heat pipe.

To explore the thermal responses under the non-thermal equilibrium cold environmental conditions, a laboratory study was conducted in climate chamber. The local skin temperatures and thermal sensation of 20 subjects were recorded at 10 min intervals for 90 min under air temperatures of 7.4, 9.1, 11 and 15 °C. The results show that both local skin temperatures and mean skin temperature decrease not only with the drop of ambient air temperature but also with the exposure time. Local thermal sensation and overall the thermal sensation have the similar temperature-varying and time-varying characteristics. Predicted mean vote (PMV) model cannot correctly predict the thermal sensation under non-thermal equilibrium cold environment. The correlation between local thermal sensation and local skin temperatures shows that thermal sensation is closely related to skin temperature. Skin temperature is an effective indicator of thermal sensation. A linear relationship model between overall thermal sensation and mean skin temperature, considering both ambient temperature and exposure time, was established in the non-thermal equilibrium cold environment, which makes the evaluation of thermal sensation more objective.

To quantify the energy consumption in the process of production, transportation and processing of energy carriers, the life cycle of building energy used can be divided into two phases: on-site phase and embodied phase. As for the embodied phase, with the data in existing statistic yearbook, the consumption items of energy production and transportation were investigated. And based on the life cycle theory, an embodied coefficient of energy carriers was proposed to quantify the embodied energy consumption. Moreover, a calculation method for the embodied coefficient of energy carriers was deduced using Leontief inverse matrix based on the existing data sources. With relevant data of 2005–2007 in China, the embodied coefficients in 2005–2007 were obtained, in which the values for natural gas and thermal power are around 1.3 and 3.1, respectively; while they are 1.03–1.08 for other selected energy carriers. In addition, it is also found that the consumption in the production and processing accounts for more than 75%.