FeCrAl(f)/HA biological functionally gradient materials (FGMs) were successfully fabricated by the hot pressing technique. Scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and bending strength test machine were utilized to characterize the microstructure, component, mechanical properties and the formation of the Ca-deficient apatite on the surface of these materials. The results indicate that an asymmetrical FeCrAl(f)/HA FGM, consolidating powders prepared by mixing HA with 3%–15% (volume fraction) is successfully prepared. Both of the matrix and FeCrAl fiber are integrated very tightly and bite into each other very deeply. And counter diffusion takes place to some extent in two phase interfaces. The elemental compositions of the FeCrAl(f)/HA FGM change progressively. Ca and P contents increase gradually with immersion time increasing, and thereafter approach equilibrium. The bone-like apatite layer forms on the materials surface, which possesses benign bioactivity, and the favorable biocompatibility can provide potential firm fixation between FeCrAl(f)/HA asymmetrical FGM implants and human bone.

A modified cellular automaton (CA) program was developed to simulate the process of dynamic recrystallization (DRX) for 23Co13Ni11Cr3Mo ultrahigh strength steel. In this model, influences of deformation parameters on hardening rate and solute drag effect were considered. Moreover, an inverse analysis method was proposed for parameters identification of dislocation model and solute drag effect based on the results of isothermal compression tests on Gleeble-1500. Then, simulated microstructures under different deformation conditions were compared with those of experiments. A good agreement is achieved. Furthermore, influences of deformation parameters on microstructure evolution for 23Co13Ni11Cr3Mo steel were investigated in details. High strain is an effective measure to refine grain and improve homogeneity. Meanwhile, the desired deformation parameters are temperature of 1000–1050 °C and strain rate of 0.008–0.01 s⁻¹ for obtaining grains smaller than 22.5 μm.

The effect of yield-to-tensile strength ratio (Y/T) on failure pressure of X70 pipeline without and with corrosion defects was investigated. The stress-strain response of materials was characterized by a power-law hardening curve. Two formulas to estimate the strain hardening exponent n for a special Y/T were obtained by least squared regression method and the influence of Y/T on n was analyzed. As an application of n-Y/T expression, the analytical solutions of burst pressure for X70 pipeline without and with corrosion defects were also obtained. The results indicate that the burst pressure of defect-free X70 pipe without corrosion defects is a function of the Y/T, pipe geometry t₀/D₀ and engineering tensile strength, and increases as Y/T or t₀/D₀ increases; whilst the burst pressure of corroded X70 pipe decreases with the increase of defect depths, d/t. Comparisons indicate that the present analytical solutions closely match available experimental and numerical data.

In order to investigate the effects of different geometrical parameters and pretightening loads on failure mode and bearing strength, a large number of single-bolted T300/QY8911 composite laminates were tested under static tension load. Box-plot was used to extract the singular testing values of bearing strength and effective statistical values were obtained. T-test method of independent samples was used to study how much pretightening loads influence bearing strength. The results show that the geometrical parameters, such as ratios of width to hole diameter (w/d) and edge distance to hole diameter (e/d), remarkably influence failure mode and bearing strength. Net-section failure will occur when w/d is smaller than 4, and shear-out failure will occur when e/d is smaller than 2. Bearing failure or bearing and shear-out combined failure will occur when w/d is greater than 4 and e/d is greater than 2. There is an optimal combination of geometrical parameters to achieve the highest bearing strength. For most of specimens, pretightening loads do not explicitly influence bearing strength.

A dense ZrC coating with the thickness of 130 μm is prepared on graphite by reactive melt infiltration. XRD and SEM analyses show that the phase composition of the coating is ZrC and it adheres well with the substrate. The influence of ZrC coating on mechanical properties of the graphite was investigated by compression tests and the results show that after the coating process, the compression strength of the coated sample is improved by 13.64% as compared with graphite sample. The improvement of the compression strength for ZrC coated sample can be associated to the increased density and the ZrC particle reinforcement due to the infiltration and reaction of the melted Zr with carbon substrate in the coating process.

Olivine LiFePO₄/C nanowires have been successfully synthesized by a simple and eco-friendly solution preparation. The phase, structure, morphology and composition of the as-prepared products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric and differential-thermogravimetric analysis (TG-DTA) and energy dispersive X-ray spectrometry (EDS) techniques, showing uniform nanowire shape of LiFePO₄/C with a diameter of 80–150 nm and a length of several microns. The heat-treated LiFePO₄/C nanowires show excellent electrochemical properties of specific discharge capacity, rate capacity and cycling stability. In particular, the LiFePO₄/C nanowires heat-treated at 400 °C show preferable first discharge specific capacity of 161 mA·h/g at 0.1C rate, while the voltage platform is 3.4 V and the first discharge specific capacity is 93 mA·h/g at 20C rate. The specific capacity retention is 98% after 50 cycles at 5C rate.

Mesoporous CeO₂ was first synthesized by hydrothermal method, and then used to synthesize different contents of CuO)_x/CeO₂ (x: molar ratio of Cu to Ce) by deposition-precipitation method. These materials were characterized by X-ray diffraction (XRD), N₂ adsorption and desorption, H₂ temperature programmed reduction (H₂-TPR) and O₂ temperature programmed desorption (O₂-TPD) to study the crystal structure, surface area, and the mechanism of CO oxidation. The results show that, on XRD patterns, no evidence of CuO diffraction peaks is present until Cu loading is increased to 20%. The BET surface area decreases noticeably with the increase of Cu content. Compared with other samples, the better reducibility and activity oxygen species of (CuO)_10%/CeO₂ coincide with its better catalytic activity.

An organic-inorganic epoxy-silica-acrylate (ESA) hybrid material was used for the consolidation of Jinsha archaeological site of Chengdu in China. The hybrid materials have multiple functional groups, such as anhydride, epoxy, hydroxyl and carboxyl, which can form networks at room temperature and result in an enhanced chemical and water resistance of the consolidated soil. With increasing of TEOS content, the hybrid materials keep colorless with only some reduction of transparency, while the hybrid materials obviously turn from moderate yellowish to brown yellow with the increase of the epoxy resin (EOR) content after 120 min UV irradiation. SEM observation indicates that the hybrid soil consolidation materials can effectively penetrate into the soil substrate, fill up most of the pores, decrease the area porosity and consolidate the Jinsha archaeological soil. The consolidation performances are in the sequence: ESA > K₂SiO₄ (PS) > tetraethyl orthosilicate (TEOS).

A FEM model for a failed industrial example of roll forging was established to analyze the generation mechanisms of the mismatch of size and shape of two spring board. To demonstrate the formulation of these defects, the bites condition and contact status between rectangular groove and workpiece during rolling the first and second spring boards were analyzed. Then, a new oval-diamond groove combining oval groove and diamond groove was presented to eliminate these defects. By analyzing field variables under the same deformation degree, the larger friction can be obtained on the contact surface of workpiece and the oval-diamond groove. The physical experiment validates that the oval-diamond groove can eliminate these defects effectively, and the size of part is in good agreement with design requirement.

The electronic structures, chemical bonding, elastic and optical properties of the novel hP24 phase WB₃ were investigated by using density-functional theory (DFT) within generalized gradient approximation (GGA). The calculated energy band structures show that the hP24 phase WB₃ is metallic material. The density of state (DOS) and the partial density of state (PDOS) calculations show that the DOS near the Fermi level is mainly from the W 5d and B 2p states. Population analysis suggests that the chemical bonding in hP24-WB₃ has predominantly covalent characteristics with mixed covalent-ionic characteristics. Basic physical properties, such as lattice constant, bulk modulus, shear modulus and elastic constants C_ij were calculated. The elastic modulus E and Poisson ratio ν were also predicted. The results show that hP24-WB₃ phase is mechanically stable and behaves in a brittle manner. Detailed analysis of all optical functions reveals that WB₃ is a better dielectric material, and reflectivity spectra show that WB₃ can be promised as good coating material in the energy regions of 8.5–11.4 eV and 14.5–15.5 eV.

A series of reduction experiments of iron ore pellets with hydrogen, carbon monoxide and their mixture were carried out in a laboratory scale shaft furnace. The sticking behavior accompanying reduction of iron ore pellets was investigated. And morphology of the sticking interface forming during reduction was analyzed by SEM equipped with EDS. In order to evaluate the effects of the temperature and gas composition on sticking properties, reduction of iron ore pellets were conducted at 800–1000 °C. The results show that the sticking strength of the pellets increases with temperature, however, decreases with hydrogen content in reducing gas. For an efficient shaft furnace operation in direct reduction (DR), relative prevention of sticking such as coating of pellets was also developed to solve sticking problem. The results show that CaO is a suitable material for the coating method.

A new tamping device which is driven by an electrohydraulic exciter was proposed to overcome the limitations of mechanically driven devices. The double-rod oscillation cylinder drives the tamping arm to realize vibration. A new spin valve was designed in order to fulfill dynamic state requirements of the oscillation cylinder. Parametric analysis was carried out by establishing mathematic model. Then, the relationships among the structure of valve port and the frequency, amplitude, output shock force of the cylinder were researched. An experimental device of the electrohydraulic exciter was established to validate the theoretical results. The signals were acquired by AVANT dynamic signal analyser of vibration. The results show that new tamping device can satisfy all kinds of complex working conditions with the flexible adjustment of frequency and amplitude.

Energy method for the vibration of two types of cylindrical shells, namely thin-walled homogeneous isotropic and manifold layered isotropic cylindrical shells under uniform external lateral pressure is presented. The study is carried out based on strain-displacement relationship from Love’s shell theory with beam functions as axial modal function. A manifold layered cylindrical shell configuration is formed by three layers of isotropic material where the inner and outer layers are stainless steel and the middle layer is aluminum. The homogeneous cylindrical shell is made-up of isotropic one layer with stainless steel. The governing equations with uniform external lateral pressure for homogeneous isotropic and manifold layered isotropic cylindrical shells are obtained using energy functional by the Lagrangian function with Rayleigh-Ritz method. The boundary conditions that are presented at the end conditions of the cylindrical shell are simply supported-simply supported, clamped-clamped and free-free. The influences of uniform external lateral pressure and symmetrical boundary conditions on the natural frequency characteristics for both homogeneous and manifold layered isotropic cylindrical shells are examined. For all boundary conditions considered, the natural frequency of both cylindrical shells with symmetric uniform lateral pressure increases as h/R ratio increases and those considering natural frequency of the both cylindrical shells with symmetric uniform lateral pressure decrease as L/R ratio increases.

A test rig for constant velocity water entry experiments was developed that drives a flatted-bottom section attached on six degree of freedom(6-DOF) platform to enter the water vertically at near constant velocity. The experiment system, which consists of drive and actuation system, water pool, model test sections, load cell, and control system, was presented. Water entry forces of different velocities were measured during impact process, and for each test case, three runs were performed with the same motion program to check the repeatability of the force readings. The experiment results are compared with two-dimensional (2D) CFD simulation methods for flatted-bottom rigid bodies with constant entry velocity. Experimental results indicate that the impact forces mainly depend on water entry velocities. It is concluded that the feasibility and accuracy of simulation methods has been validated.

The trajectory planning and tracking control for an underactuated unmanned surface vessel (USV) were addressed. The reference trajectory was generated by a virtual USV, and the error equation of trajectory tracking for underactuated USV was obtained, which transformed the tracking and stabilization problem of underactuated USV into the stabilization problem of the trajectory tracking error equation. A nonlinear state feedback controller was proposed based on backstepping technique and Lyapunov’s direct method. By means of Lyapunov analysis, it is proved that the proposed controller ensures that the solutions of closed loop system have the ultimate boundedness property. Numerical simulation results are presented to validate the effectiveness and robustness of the proposed controller.

Inherent flaws in the extended Kalman filter (EKF) algorithm were pointed out and unscented Kalman filter (UKF) was put forward as an alternative. Furthermore, a novel adaptive unscented Kalman filter (AUKF) based on innovation was developed. The three data-fusing approaches were analyzed and evaluated in a mathematically rigorous way. Field experiments conducted in lake further demonstrate that AUKF reduces the position error approximately by 65% compared with EKF and by 35% UKF and improves the robust performance.

A methodology for topology optimization based on element independent nodal density (EIND) is developed. Nodal densities are implemented as the design variables and interpolated onto element space to determine the density of any point with Shepard interpolation function. The influence of the diameter of interpolation is discussed which shows good robustness. The new approach is demonstrated on the minimum volume problem subjected to a displacement constraint. The rational approximation for material properties (RAMP) method and a dual programming optimization algorithm are used to penalize the intermediate density point to achieve nearly 0-1 solutions. Solutions are shown to meet stability, mesh dependence or non-checkerboard patterns of topology optimization without additional constraints. Finally, the computational efficiency is greatly improved by multithread parallel computing with OpenMP.

The dynamic model of cold rolling mill based on strip flatness and thickness integrated control was proposed, containing the following sub-models: the rolling process model, the dynamic model of rolls along axial direction, and the compensation model. Based on the rule of volume flow rate, the dynamic rolling process model was built. The work roll and backup roll were taken as elastic continuous bodies, the effect of shear and moment of inertia were taken into consideration, and then the dynamic model of rolls was built. The two models were coupled together, and the dynamic model of rolling mill was built. In the dynamic model, the thermal expansion of the rolls, the wear of the rolls and other related parameters can not be considered. In order to compensate the dynamic model, the coupled static model of rolls and strip was applied. Then, according to the inner relationship of these models, the dynamic model and the compensation model were coupled, and the dynamic model of rolling mill based on the strip flatness and thickness integrated control was built. The dynamic simulation of the rolling process was made, and the dynamic thickness and the dynamic flatness information were obtained. This model not only provides a theory basis for the virtual rolling, but also provides a platform for the application of advanced control theory.

A novel approach was proposed to allocate spinning reserve for dynamic economic dispatch. The proposed approach set up a two-stage stochastic programming model to allocate reserve. The model was solved using a decomposed algorithm based on Benders’ decomposition. The model and the algorithm were applied to a simple 3-node system and an actual 445-node system for verification, respectively. Test results show that the model can save 84.5 US $ cost for the testing three-node system, and the algorithm can solve the model for 445-node system within 5 min. The test results also illustrate that the proposed approach is efficient and suitable for large system calculation.

The tunnel field-effect transistor (TFET) is a potential candidate for the post-CMOS era. As one of the most important electrical parameters of a device, double gate TFET (DG-TFET) gate threshold voltage was studied. First, a numerical simulation study of transfer characteristic and gate threshold voltage in DG-TFET was reported. Then, a simple analytical model for DG-TFET gate threshold voltage V_TG was built by solving quasi-two-dimensional Poisson equation in Si film. The model as a function of the drain voltage, the Si layer thickness, the gate length and the gate dielectric was discussed. It is shown that the proposed model is consistent with the simulation results. This model should be useful for further investigation of performance of circuits containing TFETs.

In order to enhance measuring precision of the real complex electromechanical system, complex industrial system and complex ecological & management system with characteristics of multi-variable, non-liner, strong coupling and large time-delay, in terms of the fuzzy character of this real complex system, a fuzzy least squares support vector machine (FLS-SVM) soft measurement model was established and its parameters were optimized by using adaptive mutative scale chaos immune algorithm. The simulation results reveal that fuzzy least squares support vector machines soft measurement model is of better approximation accuracy and robustness. And application results show that the relative errors of the soft measurement model are less than 3.34%.

An effective and simple way to develop equations from impact strain signals was proposed. Little research has been performed in this area, but this equation is very important for evaluating input signals in finite element analysis impact tests and for obtaining additional information on material deformation and fracture processes under impact loading. For this purpose, dynamic impact responses were examined through signals obtained from a strain gauge installed on an impact striker connected to a data acquisition system. Aluminium 6061-T6 was used to extract strain responses on the striker during Charpy impact testing. Statistical analysis was performed using the I-kaz method, and curve fitting equations based on the equation for vibration response under a non-periodic force were used to evaluate the Charpy impact signals. The I-kaz coefficients and curve fitting equations were then compared and discussed with related parameters, such as velocities and thicknesses. Velocity and thickness were found to be related to the strain signal patterns, curve fitting equations and I-kaz coefficients. The equations developed using this method had R² values greater than 97.7%. Finally, the constructed equations were determined to be suitable for evaluating Charpy impact strain signal patterns and obtaining additional information on fracture processes under impact loading.

In order to improve the resource allocation mechanism of artificial immune recognition system (AIRS) and decrease the memory cells, a fuzzy logic resource allocation and memory cell pruning based AIRS (FPAIRS) is proposed. In FPAIRS, the fuzzy logic is determined by a parameter, thus, the optimal fuzzy logics for different problems can be located through changing the parameter value. At the same time, the memory cells of low fitness scores are pruned to improve the classifier. This classifier was compared with other classifiers on six UCI datasets classification performance. The results show that the accuracies reached by FPAIRS are higher than or comparable to the accuracies of other classifiers, and the memory cells decrease when compared with the memory cells of AIRS. The results show that the algorithm is a high-performance classifier.

In multi-agent systems (MAS), finding agents which are able to service properly in an open and dynamic environment are the key issue in problem solving. However, it is difficult to find agent resources quickly and position agents accurately and complete the system integration by the keyword matching method, due to the lack of clear semantic information of the classical agent model. An semantic-based agent dynamic positioning mechanism was proposed to assist in the system dynamic integration. According to the semantic agent model and the description method, a two-stage process including the domain positioning stage and the service semantic matching positioning stage, was discussed. With this mechanism, proper agents that provide appropriate service to assign sub-tasks for task completion can be found quickly and accurately. Finally, the effectiveness of the positioning mechanism was validated through the in-depth performance analysis in the application of simulation experiments to the system dynamic integration.

In view of the uncertainty and complexity, the intelligent model of rehabilitation training program for stroke was proposed, combining with the case-based reasoning (CBR) and interval type-2 fuzzy reasoning (IT2FR). The model consists of two parts: the setting model based on CBR and the feedback compensation model based on IT2FR. The former presets the value of rehabilitation training program, and the latter carries on the feedback compensation of the preset value. Experimental results show that the average percentage error of two rehabilitation training programs is 0.074%. The two programs are made by the intelligent model and rehabilitation physician. That is, the two different programs are nearly identical. It means that the intelligent model can make a rehabilitation training program effectively and improve the rehabilitation efficiency.

Multi-target tracking (MTT) is a research hotspot of wireless sensor networks at present. A self-organized dynamic cluster task allocation scheme is used to implement collaborative task allocation for MTT in WSN and a special cluster member (CM) node selection method is put forward in the scheme. An energy efficiency model was proposed under consideration of both energy consumption and remaining energy balance in the network. A tracking accuracy model based on area-sum principle was also presented through analyzing the localization accuracy of triangulation. Then, the two models mentioned above were combined to establish dynamic cluster member selection model for MTT where a comprehensive performance index function was designed to guide the CM node selection. This selection was fulfilled using genetic algorithm. Simulation results show that this method keeps both energy efficiency and tracking quality in optimal state, and also indicate the validity of genetic algorithm in implementing CM node selection.

A novel approach is proposed for improving adaptive feedback cancellation using a variable step-size affine projection algorithm (VSS-APA) based on global speech absence probability (GSAP). The variable step-size of the proposed VSS-APA is adjusted according to the GSAP of the current frame. The weight vector of the adaptive filter is updated by the probability of the speech absence. The performance measure of acoustic feedback cancellation is evaluated using normalized misalignment. Experimental results demonstrate that the proposed approach has better performance than the normalized least mean square (NLMS) and the constant step-size affine projection algorithms.

A novel cast shadow detection approach was proposed. A stereo vision system was used to capture images instead of traditional single camera. It was based on an assumption that cast shadows were on a special plane. The image obtained from one camera was inversely projected to the plane and then transformed to the view from another camera. The points on the plane shared the same position between original image and the transformed image. As a result, the cast shadows can be detected. In order to improve the efficiency of cast shadow detection and decrease computational complexity, the obvious object areas in CIELAB color space were removed and the potential shadow areas were obtained. Experimental results demonstrate that the proposed approach can detect cast shadows accurately even under various illuminations.

A shadow detection method using pulse couple neural network inspired by the characters of human visual system is proposed. More precisely, lateral inhibition of human vision and coefficient of variation are combined together to improve the pulse couple neural network. Shadow detection is considered to be a shadow region segmentation problem. Experiment shows that the presented method is consistent with human vision compared to shadow detection methods based on HSV and pulse couple neural network (PCNN) by both subjective and objective assessments.

Some novel grooved-sintered composite wick heat pipes (GSHP) were developed for the electronic device cooling. The grooved-sintered wicks of GSHP were fabricated by the processes of oil-filled high-speed spin forming and solid state sintering. The wick could be divided into two parts for liquid capillary pumping flow: groove sintered zone and uniform sintered zone. Both of the thermal resistance network model and the maximum heat transfer capability model of GSHP were built. Compared with the theoretical values, the heat transfer limit and thermal resistance of GSHP were measured from three aspects: copper powder size, wick thickness and number of micro grooves. The results show that the wick thickness has the greatest effect on the thermal resistance of GSHP while the copper powder size has the most important influence on the heat transfer limit. Given certain copper powder size and wick thickness, the thermal resistance of GSHP can be the lowest when micro-groove number is about 55.

In order to present a new method for plugging channeling in oil field, the injection modes and validity period of foam system which plugged the formation water layer were studied by means of the experimental model which simulated the real conditions of oil wells existing channeling. Above all, the influence factors including reservoir pressure, permeability, oil saturation and gas-to-liquid ratio were studied through dynamic experiment. Then, in light of the technology characteristics of foam injection in oil field, the comparison between gas-liquid and liquid-gas injection modes was studied. The result shows that the gas-liquid injection mode can ensure the foam injectivity and plugging performance. The plugging validity of nitrogen foam injected into the formation water layer was evaluated in different plugging pressure gradients by the dynamic method which is more reasonable than the static evaluation method in laboratory. The research demonstrates that the plugging validity period of foam decreases with plugging pressure gradient increasing. If the plugging pressure gradient is 0.15 MPa/m, the validity period is 160 h. Finally, a empirical equation and a plate about the plugging validity and the plugging pressure gradient were obtained for forecasting the validity period of foam.

Experimental design was applied in the optimization of crude oil adsorption from saline waste water using raw bagasse. The application of response surface methodology (RSM) was presented with temperature, salinity of water, pH, adsorbent dose, and initial oil content as factors. A quadratic model could be used to approximate the mathematical relationship of crude oil removal on the five significant independent variables. Predicted values and experimental values are found to be in good agreement with R² of 97.44%. The result of optimization shows that the maximum crude oil removal is equal to 67.38% under the optimal condition of temperature of 46.53 °C, salinity of 37.2 g/L, pH of 3, adsorbent dose of 9 g/L and initial oil content of 300×10⁻⁶.

Acidic deposition, which is mainly caused by atmospheric pollution, is one of the global environmental problems. Thinning is an effective management to improve the tree productivity, reduce the wildfire risk and maintain a healthy forest. Since thinning may reduce the effect of acidic deposition, the effect of thinning on acidic deposition was estimated. The biomass, soil properties, pH value of runoff and groundwater in both unthinned and thinned Chinese fir plantations were measured and compared over a 5-year period (2–6 years after thinning). The results indicated that acidic deposition in the Huitong State Ecosystem Research Station was serious, and it got worse with time. Forest thinning resulted in a huge change in biomass and soil properties. During the 5-year monitoring period, biomasses of understory and litter, plant species richness, coverage of undergrowth plant layer were significantly higher in thinned site than in unthinned site. Moreover, higher soil fertility as well as lower amounts of runoff and groundwater were found in thinned site. It was suggested that thinning could improve the structure of forest, leading to restoring the effluent (runoff and groundwater) pH to the normal value.

A decomposition model was applied to study the resource-saving and environment-friendly effects of air pollutant emissions (taking industrial SO₂ emission as an example) in China. From the results, it is found that 38.93% and 61.07% are contributed to environment-friendly and resource-saving effects, respectively, by the dramatic decrease in industrial SO₂ emission density (nearly 70% from 2001 to 2010). This indicates that China has achieved important progress during the 11th FYP (five-year plan) compared with the 10th FYP. A simultaneous equations model was also employed to analyze the influencing factors by using data from 30 provinces in China. The results imply that the influence of environmental regulation on environment-friendly effect is not obvious during the 10th FYP but obvious during the 11th FYP. Thus, the government should continue promoting the environment-friendly effect by further enhancing environmental regulation and strengthening the role of environmental management.

Based on structural surface normal vector spherical distance and the pole stereographic projection Euclidean distance, two distance functions were established. The cluster analysis of structure surface was conducted by the use of ATTA clustering methods based on ant colony piles, and Silhouette index was introduced to evaluate the clustering effect. The clustering analysis of the measured data of Sanshandao Gold Mine shows that ant colony ATTA-based clustering method does better than K-mean clustering analysis. Meanwhile, clustering results of ATTA method based on pole Euclidean distance and ATTA method based on normal vector spherical distance have a great consistence. The clustering results are most close to the pole isopycnic graph. It can efficiently realize grouping of structural plane and determination of the dominant structural surface direction. It is made up for the defects of subjectivity and inaccuracy in icon measurement approach and has great engineering value.

Three representative sulfide ore samples were collected from typical metal mines, and their corresponding pre-oxidized products were obtained under nature environment. The thermal behaviors of each sample at heating rates of 5, 10, 15 and 20 °C/min in air flow from ambient temperature to 800 °C were studied by simultaneous thermal analysis and the TG/DSC curves before and after the pre-oxidation were compared. By the peak temperature of DTG curves, the whole reaction process for each sample was divided into different stages, and the apparent activation energies were calculated by the Ozawa-Flynn-Wall method. The results show that the reaction process of each sample after pre-oxidation is more complex, with quicker reaction rates, fewer heat production quantities, and higher or lower ignition-points. The apparent activation energies decrease from 364.017–474.228 kJ/mol to 244.523–333.161 kJ/mol. Therefore, sulfide ores are more susceptible to spontaneous combustion after the pre-oxidation.

The specific results of the work investigating the effect of gas density and water temperature on bubble size were present. These were surrogate variables designed to investigate the effect of viscosity (varying water temperature) and altitude (varying gas density). The results show that there is a measurable but relatively small effect of gas density on bubble size. The D₃₂ is revealed to increase proportionally as (ρ₀/ρ_g)^0.132. The projected impact on flotation kinetics at 4500 m versus sea level is small, of the order of 0.5% recovery loss for a bank of eight flotation cells. The effect of water temperature (4–40 °C) on bubble size is more significant than gas density. The relationship correlates with water viscosity values quite closely. A finding that D₃₂ increases proportionally as (µ/µ₂₀)^0.776 highlights the importance of accounting for viscosity effects if, for example, large process temperature fluctuations or deviation from design/test conditions are expected.

The grown conditions of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans were investigated, and then experiments were conducted to research the bioleaching behaviors of crude ore of copper sulfide and hand-picked concentrates of chalcopyrite by Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans. The experimental results show that the bacteria grow best when the temperature is (30±1) °C and the pH value is 2.0. The bacteria concentration is 2.24×10⁷ mL⁻¹ in this condition. It is found that the copper extraction yield is affected by the inoculum size and the pulp density and the extraction yield increases as the inoculum size grows. The bioleaching rates reach their highest point in sulfide copper and chalcopyrite with a pulp density of 5% and 10%, respectively. Column flotation experiments of low-grade copper sulfide ores show that the bioleaching recovery reaches nearly 45% after 75 days.

In order to reveal the relationship between the penecontemporaneous karstification and sedimentary microtopography in sequence stratigraphy, the sequence stratigraphic framework of Lianglitage formation in Upper Ordovician is studied according to the well drilling, logging, geophysical data, detailed observations of core and the paleontology. The Lianglitage formation belongs to the sequence IV of Ordovician. The second member of Lianglitage formation is prograde sedimentation in highstand systems tract, and is favorable for developing reef flat. The development scale and thickness of reef flat are controlled by the variation of secondary sea level. The types and characteristics of karst in the highstand systems tract show that the late highstand systems tract is dissolved and cemented by the meteoric fresh water and mixed water. Penecontemporaneous karstification is developed at the top of parasequence and high place of geomorphology. Atmospheric diagenetic lens is formed. The developing regulations and controlling factors of penecontemporaneous karstification can provide new clues to the prediction and exploration of favorable reservoir in this area.

Reservoirs can be developed in the sediment gravity flows. However, high quality reservoirs are found widespread in sediment gravity flows of Gangzhong area, Huanghua depression, Bohai Bay Basin, East China. Characteristics and formation of these reservoirs are key problems to be solved. Through comprehensive analysis of thin section petrography, scanning electron microscopy and X-ray diffraction, two distinct rules were obtained. 1) These high quality reservoirs have apparent characteristics: lithology consists mainly of medium-fine grained sands; moderately-well sorted and rounded; intergranular pores dominating >70% of the entire pores, surface per unit pore volume reaches 15%; average porosity is 21% and average permeability is 55×10⁻³ μm². 2) Types of sedimentary microfacies and dissolution strongly control on the formation of high quality reservoirs. Main channels and sandy braided bars have the best reservoir properties. Because that sediments are mainly medium-fine grained sands in high-energy environments. The favorable primary porosity and permeability may promote calcite cementation and help to produce more secondary pores. Besides, at the depth of 2500–3200 m, basically matching threshold of oil generation, organic acid expelled when organic matter became mature, and H⁺ released during clay mineral transformation. These both result in the dissolution of calcite cements and create large volume pores, then physical properties improve correspondingly. Moreover, deep hydrothermal fluid intrusion may also have impacts on the development of secondary pores.

Influence of identical applied initial pressures on the radial surfaces of a hollow cylinder which is compose of materials with first power hypo-elastic constitutive model was investigated. The basic equations of the problem were built up based on the framework of piecewise homogeneous body model with the use of three-dimensional linearized theory of elastic waves in initially stressed bodies (TLTEWISB). With the method proposed previously, this problem was then solved numerically. Moreover, the dispersion group velocity of the lowest order mode with different initial pressures was also studied. It can be concluded that the initial pressure and the geometry parameters will induce considerable changes of different degrees in dispersive relation between phase velocity and wave number in opposite trend (positive in initial pressure and negative in thickness).

Design and construction of engineering structures in geomaterials with block-in-matrix texture (referred as bimrock) such as conglomerates, breccias and agglomerates are challenging tasks for engineers. When dealing with these materials in important structures such as open pits with high walls and pillars of deep underground mines, understanding the complete stress-strain behavior, including post-peak region, is a formidable yet crucial engineering practice. To study the post-peak behavior of bimrocks, artificial specimens were fabricated with a mixture of rock blocks and a cementing agent. All the experiments were conducted under uniaxial compression using a servo-control testing machine. The results show that the specimens with the highest block proportion (around 90% by mass) showed a small decrease in stress with strain increment in the post-peak region. The specimens with lower block proportions were characterized by an approximately steep fall in stress and following to residual stress. Based on the study, it is inferred that all the artificial specimens undergo post-failure deformation and the type of post behavior depends on rock block proportions.

Steel shear wall (SSW) was properly determined using numerical and experimental approaches. The properties of SSW and LYP (low yield point) steel shear wall (LSSW) were measured. It is revealed that LSSW exhibits higher properties compared to SSW in both elastic and inelastic zones. It is also concluded that the addition of CFRP (carbon fiber reinforced polymers) enhances the seismic parameters of LSSW (stiffness, energy absorption, shear capacity, over strength values). Also, stress values applied to boundary frames are lower due to post buckling forces. The effect of fiber angle was also studied and presented as a mathematical equation.

Methodology for the reliability analysis of hydraulic gravity dam is the key technology in current hydropower construction. Reliability analysis for the dynamical dam safety should be divided into two phases: failure mode identification and the calculation of the failure probability. Both of them are studied based on the mathematical statistics and structure reliability theory considering two kinds of uncertainty characters (earthquake variability and material randomness). Firstly, failure mode identification method is established based on the dynamical limit state system and verified through example of Koyna Dam so that the statistical law of progressive failure process in dam body are revealed; Secondly, for the calculation of the failure probability, mathematical model and formula are established according to the characteristics of gravity dam, which include three levels, that is element failure, path failure and system failure. A case study is presented to show the practical application of theoretical method and results of these methods.

New-old concrete composite system usually exists in concrete repairing structure. In the present work, series of experiments were carried out to investigate permeability and ion diffusion properties of new-old concrete composite by measuring 6-hour coulomb charge and chloride diffusivity. The interrelation among transport properties of new-old composites, new, and old concretes was also discussed. Results indicate that the permeability and chloride diffusivity of new-old concrete composite system closely interrelate to the corresponding new concrete and old concrete. The interfacial transition zone between new concrete and old concrete greatly influences the transport property of new-old concrete system. Compared with the corresponding new concrete and old concrete lower permeability and diffusivity values for the new-old concrete composites can be achieved by choosing suitable new concrete. It is possible to design the tailor-made new-old concrete composite system for repair given the transport property.

Particle size distributions of obtained samples from several sampling campaigns were determined and raw data were mass balanced before being used in simulation studies. After determination of breakage function, selection function, Bond work index, residence time distribution parameters, and Whiten’s model parameters for air separators and diaphragms between the two compartments of tube ball mills, performance of the circuits was simulated for given throughputs and feed particle size distribution. Whiten’s model parameters were determined by GA (genetic algorithm) toolbox of MATLAB software. Based on implemented models for modeling and simulation, optimization of circuits was carried out. It increased nearly 10.5% and 15.8% in fresh feed capacity input to each tube ball mill. In addition, circulating load ratios of circuits are modified to 118% and 127% from low level of 57% and 22%, respectively, and also cut points of air separators are adjusted at 30 and 40 μm from high range of 53 and 97 μm, respectively. All applications helped in well-operation and energy consumption reduction of equipments.

A novel engineered cementitious composite (ECC) was prepared with the complex binder of Portland cement and asphalt emulsion. By adjusting the amount of asphalt emulsion, different mixture proportions were adopted in experiments, including four-point bending test, compressive test, and scanning electric microscopy (SEM). The SEM observation was conducted to evaluate the contribution of polyvinyl alcohol (PVA) fiber and asphalt emulsion to the composite toughening mechanism. The tests results show that the most remarkable deflection-hardening behavior and saturated multiple cracking are achieved when the content of asphalt emulsion is 10%. However, excessive content of asphalt emulsion causes severe damages on the deformation behavior as well as loss in compressive strength of the mixture. SEM observation indicates that the influence of asphalt emulsion on the fiber/matrix interfacial property changes the dominant fiber failure type from rupture into pull-out mode, and thus causes beneficial effects for strain-hardening behavior.

The compaction and stress generation on terrain were always investigated based on empirical approaches or testing methods for tire/soil interaction. However, the analysis should be performed for various tires and at different soil strengths. With the increasing capacity of numerical computers and simulation software, finite element modeling of tire/terrain interaction seems a good approach for predicting the effect of change on the parameters. In this work, an elaborated 3D model fully complianning with the geometry of radial tire 115/60R13 was established, using commercial code Solidwork Simulation. The hyper-elastic and incompressible rubber as tire main material was analyzed by Moony-Rivlin model. The Drucker-Prager yield criterion was used to model the soil compaction. Results show that the model realistically predicts the laboratory tests outputs of the modeled tire on the soft soil.

The route optimization problem for road networks was applied to pedestrian flow. Evacuation path networks with nodes and arcs considering the traffic capacities of facilities were built in metro hubs, and a path impedance function for metro hubs which used the relationships among circulation speed, density and flow rate for pedestrians was defined. Then, a route optimization model which minimizes the movement time of the last evacuee was constructed to optimize evacuation performance. Solutions to the proposed mathematical model were obtained through an iterative optimization process. The route optimization model was applied to Xidan Station of Beijing Metro Line 4 based on the actual situations, and the calculation results of the model were tested using buildingExodus microscopic evacuation simulation software. The simulation result shows that the proposed model shortens the evacuation time by 16.05%, 3.15% and 2.78% compared with all or none method, equally split method and Logit model, respectively. Furthermore, when the population gets larger, evacuation efficiency in the proposed model has a greater advantage.

Traffic jam in large signalized road network presents a complex nature. In order to reveal the jam characteristics, two indexes, SVS (speed of virtual signal) and VOS (velocity of spillover), were proposed respectively. SVS described the propagation of queue within a link while VOS reflected the spillover velocity of vehicle queue. Based on the two indexes, network jam simulation was carried out on a regular signalized road network. The simulation results show that: 1) The propagation of traffic congestion on a signalized road network can be classified into two stages: virtual split driven stage and flow rate driven stage. The former stage is characterized by decreasing virtual split while the latter only depends on flow rate; 2) The jam propagation rate and direction are dependent on traffic demand distribution and other network parameters. The direction with higher demand gets more chance to be jammed. Our findings can serve as the basis of the prevention of the formation and propagation of network traffic jam.