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The hot deformation of TA15 titanium alloy was studied by the hot compression test on the Gleeble-3800 thermal simulation equipment. The true stress-strain curves of TA15 titanium alloy at the temperature of 1123-1223K and the strain rate of 0.001-1s-1 were obtained.. The results show that the flow stress increases with decreasing temperature, and increases as the strain rate increases. And the deformation process is accompanied by work hardening and dynamic recovery and dynamic recrystallization. Based on the true stress-strain curves of TA15 titanium alloy, the Arrhenius-typed constitutive equation was established. The thermal deformation activation energy of TA15 titanium alloy with a strain of 0.2 is 746.27kJ/mol.

The transparent β-Si3N4ceramic with a whisker-like microstructure was prepared by hot-pressing at 2000 °C for 26 h, with MgSiN2as an additive. The resultant material achieves the maximum transmittance of 70 % at the wavelength of about 2.5 μm and the transmittance value keeps higher than 60 % in the range of 700-4500 nm wavelength, which is attributed to the very small amount of the intergranular amorphous phase along with high density. The present transparent β-Si3N4ceramic exhibits an indentation fracture toughness of 7.2±0.3 MPa m1/2.

When tunneling deep sandstone roadway of-350m level in Yongrong mining area, it appears frequent occurrence of rock burst and gas dynamic phenomenon. Through discussing tectonic stress field, tunneling stress field, self-weight stress field and physico-mechanical properties of middle-fine sandstone, this paper draws sandstone outburst mechanism with rock drivage in mine coal-bearing.

Because of the complex processes and the high cost of rock geophysical properties tested in laboratory, an intelligent method based on hybrid dimensionality reduction with Elman neural networks was proposed to estimate the geophysical parameters of sandstone. Firstly, the grey correlation analysis is used to calculate the correlation between rock slice feature parameters and geophysical properties to select some parameters with high correlation; secondly, the principal component analysis is used for once more dimension reduction based on the selected feature parameters; finally, the Elman neural networks is applied to find the mapping relationship between rock slice feature parameters and geophysical properties within it. The result showed that the average relative errors of porosity and permeability were 7.28% and 6.25% respectively.

Gradient-porous Titanium alloys can be applied to manufacturing implants for bone replacement, due to their good biological and mechanical compatibility. In this work, the feasibility of fabricating gradient-porous Titanium by centrifugal deposition and vacuum sintering was investigated. The apparent porosity of the gradient-porous Ti examined by Archimedes method is 56%. And the open pores occupy 89%. The pore structure was observed by an optical microscope. And its porosities at different radius were calculated by image software based on optical microscopic images. In addition, a nanoindentation was employed to characterize the mechanical properties at different radius. The results showed that the porosity of the sample increased with increasing of radius. Besides, both the elastic modulus and hardness changed alone radius with a same trend.

Because of the inherent conflict between visual area and resolution in rock microscope structure, during the study of the RCTS (Rock Core Thin Section) microstructure, we cannot focus on the multi-scale structure characteristics of the particles, pores and throats, and it is fail to satisfy the demands of a more comprehensive study. In order to solve this problem, a microscopic image stitching method in RCTS is proposed by applying SIFT (Scale Invariant Feature Transform) detection algorithm. This method can successfully solve the conflict between the visual area and resolution, overcoming the problem of inclining and deformation in images acquisition under the microscope and finally, achieving the seamless stitching of RCTS microscopic image for big visual area. The experimental results show that this method can improve the accuracy of rock analysis in microstructure and has important practical and theoretical significance for the development of tight sandstone reservoir.

The purpose of this article is to select the most appropriate sensor for the crane structural health monitoring. We used three kinds of sensors to do an equal strength beam test: The original sensor R2 and R4 which have been calibrated, American MOI FBG sensor and wireless strain sensor. After derived the formula of maximum normal strain, we have done equal strength beam test for 3 times. Then calculated their average and contrasted their linearity to see the accuracy of MOI FBG os3110 and wireless sensor. Compared with the experimental value theoretical value, the wireless sensor has the highest accuracy, it is even more accuracy than the original sensor R2 and R4 which have been calibrated; Departure from linearity aspect, the wireless sensor, the original sensor R2 and R4,all of them have small relative error rate, it is less than 10%, but MOI FBG os3110 has very large relative error rate; In order to compare the overall performance of the sensor, we can also compare the sensors from the sensitivity aspect, zero drift, detection range, and so on.

In order to implement the recognition automation of rock section pore images, a method combined K-means clustering with probabilistic neural network is proposed and applied to rock thin section images. Firstly, K-means clustering is used as segmentation algorithm, the rock images are divided into two types and extracted enough features and it is shown good classification recognition effect on testing dataset. Secondly, 100 pieces of rock image section are used as validation dataset, including 20 groups, each group has 5 images and 200 data samplings. Experiments show that the probabilistic neural network can be used as rock texture classifier, the average correct classification rate is around 95.12%, which can meet the practical application needs.

For the identification complexity of rock microstructure, based on numerical analysis of rock section images, an automatic rock texture classification method and identification system is proposed in this paper. Digital grey image processing of rock thin section is used for features extraction, the features are then as inputs to the neural network model, the model output is the rock microstructure classification. 100 pieces of rock section images from Sulige region in Changqing Oilfield are used for the experiment; the whole dataset is randomly divided into 70 images for training datasets, 15 images for validation datasets and 15 images for testing datasets. It is shown that the correct classification rate for automatic identification of rock microstructure is about 93.3%. Therefore, the proposed method for solving geological problem is effective and can get a good identification performance for rock microstructure classification quickly and accurately.

With the global temperatures continue to rise, the days of hot weather were increasing, people who works in high-temperature and high-humidity environment will be injured. The heat damage will affect the person's behavior ability, decrease the staff’s working ability and cause misoperation. Comprehensive analysis of the factors of all aspects is very important for the analysis of heat damage risk to human. The analytic hierarchy process (AHP) method is used to analyze the problem in five aspects which are the physiological and psychological characteristics, work factors, work characteristics, work environment. The scores and the total score are calculated. Five classes classification method is used to establish the system of the individual risk evaluation model of heat damage pathogenic. The corresponding improvement strategies are provided to ensure the worker safety.

This paper investigates a composite cathode La0.2Sr0.8TiO3+δ-Ce0.8Sm0.2O2-δ (LSTO-SDC) for the direct steam electrolysis in an oxide-ion-conducting solid oxide electrolyzer. The dependences of electrical conductivity of the reduced LSTO on temperature and oxygen partial pressure are studied and further correlated to the electrochemical properties of the cathode in symmetric cell LSTO-SDC/YSZ/LSTO-SDC and solid oxide electrolyzer LSTO-SDC/YSZ/LSM-SDC, respectively. Current efficiencies of the solid oxide electrolyzer with LSTO-SDC cathode were found to be 92.38% and 91.17% with or without reducing gas flowing over them under the applied voltage of 1.8 V at 800 °C, respectively.

In order to solve the problem of uncertain cycle of water injection in the oilfield, this paper proposed a numerical method based on PCA-FNN, so that it can forecast the effective cycle of water injection. PCA is used to reduce the dimension of original data, while FNN is applied to train and test the new data. The correctness of PCA-FNN model is verified by the real injection statistics data from 116 wells of an oilfield, the result shows that the average absolute error and relative error of the test are 1.97 months and 10.75% respectively. The testing accuracy has been greatly improved by PCA-FNN model compare with the FNN which has not been processed by PCA and multiple liner regression method. Therefore, PCA-FNN method is reliable to forecast the effectiveness cycle of water injection and it can be used as an decision-making reference method for the engineers.

In this paper, the author introduced resonance mechanism into the stability analysis of power system, established comprehensive mathematical model including units and power grids by considering the effects from generation side and line side. On this basis, the author simulated several typical disturbances to analysis by MATLAB SIMULINK. The result showed that the power oscillation will be caused when the natural frequency of the grid and the frequency of disturbances are same or similar, especially in multi-area interconnected power system. The disturbances from different units can produce a significant impact transient or sustained oscillation by superposition, endanger the stability of power system.

In order to study the typical fault types of Field (Factory) Special Motor Vehicle in the inspection process, we visited many warehouses and wharves in Huangpu District for inspection research, then summarizedthe typical failure modesand took its failure causes and treatment measures for key research. First, wemade statistics and summarized the failure law according to the typical fault types among the old vehicles of annual test. Then we analyzed the concrete manifestation and summarized the failure causes from the braking performance, knuckle mechanic, tire wear, fork loose and other failures of forklift. Then we aimed at the new vehicles of test and acceptance of fault type for statistical analysis. Finally, weformulate corresponding measures according to different fault types. As the result of Inspection and investigation showed, the failure rate of electric forkliftreaches to 1.3% as the failure rate of diesel forklift is to 10.7%; the market share of electric forklift of test and acceptance rose from 41.6% to 78.3% compared with electric forklift of annual test. Braking deviation oflinear acceleration is the most typical fault type of forklift; electric forklift make more excellent performance than diesel forklift on key parameterssuch as braking; forward forklift easily has rollover accidents.

By proposing a numerical based method on PCA-ANFIS(Adaptive Neuro-Fuzzy Inference System), this paper is focusing on solving the problem of uncertain cycle of water injection in the oilfield. As the dimension of original data is reduced by PCA, ANFIS can be applied for training and testing the new data proposed by this paper. The correctness of PCA-ANFIS models are verified by the injection statistics data collected from 116 wells inside an oilfield, the average absolute error of testing is 1.80 months. With comparison by non-PCA based models which average error is 4.33 months largely ahead of PCA-ANFIS based models, it shows that the testing accuracy has been greatly enhanced by our approach. With the conclusion of the above testing, the PCA-ANFIS method is robust in predicting the effectiveness cycle of water injection which helps oilfield developers to design the water injection scheme.

In order to study the sensor distribution program in health monitoring of side forklift steering, we visited many ports and warehouses for inspection of side forklift steering safety in Huangpu district of Guangzhou, and summarized the most dangerous part of steering failure. Then we built a model of the steering mechanism which was simplified, and did motion simulation analysis .Then the dynamic simulation analysis was carried out on the ball pin. Finally, through the simulation calculation of maximum stress under various working conditions, we can determine the position of sensors stationing, and it provided with the train of thought of sensors distribution in health monitoring of side forklift steering mechanism.

A new kind of proportional and fuzzy classification method has been proposed in the paper, Which can be applied in the data pretreatment of neural network calculation. It is showed that this new method can keep same convergent speed of training key point, It can improve predictive precision effectively and make the predictive results approach actual value.

With the rapid development of economy and society, more and more environmental problems exposed, it all will threatened to our survival. So we should carry out a series of energy saving and emissions reduction work immediately, to create a conservation-minded society. This paper combined with the software which called Weather Tool to analysis, to find out suitable energy saving measures for university zone in Hangzhou.

Based on current research basis at home and abroad, in order to improve the level of safety technology and safeguard work efficiency, Internet of Things is brought into crane structural health monitoring. Crane structural health risk level evaluation criteria and structural health warning technology expert system are the two key aspects of the project. The mechanical properties of Q235 were studied and theoretical calculations were done by the technologies of ANSYS and ADAMS, finally the threshold was determined. Signals are collected by FBG sensors and transmitted to a demodulator, and then use software calculates the real-time stress by a formula we given in. Finally the real-time stress in different parts of the crane is acquired. If the real-time stress exceeds the allowable stress we set, it issues an alarm signal to the operators.

The sublevel caving mining method is widely applied in China's underground mines, in particular of iron mines. Its mining work is under the protection of loose coverage rock. The loose coverage rock is located in the stope for a long time, and its frequently squeezed from production blasting, impact effect and the colliding and breaking in the falling process, it comes into being a large number of powder and small pieces of rocks. The rock powder and small fragments have such characteristics-good mobility and strong permeability. With the increasement of mining depth, the rock powder and small fragments in the loose coverage rock will be earlier to reach the ores than the big fragments of the same level. As a result, ore dilution will prematurely appear. To better know the phenomenon, this paper explores ore dilution of different fragment distribution of loose coverage rock by physical simulation experimental method. The research results have certain guiding significance for the actual production of underground mines.

In this work, the mechanical properties, such as Vickers microhardnessHv, fracture toughnessKc, yield strengthσvand brittleness indexBi, of oriented 6H-SiC crystal are systematically evaluated using a microindentation technique under 0.1-2 kg applied load. It is found theHvis decreased as the applied load is increased which is mainly attributed to the effect of indenter penetration. TheHvvalue can be effectively presumed by Kicks law and the Meyers indexnis determined to be 1.73. However, theKcvalue is measured nearly a constant (~0.148 MPa.m1/2) which reveals the toughness of 6H-SiC(0001)crystal is much weaker than those of Si(100)and GaAs(100)crystals. The variation ofσvto the load is similar to that ofHv. The brittleness indexBialso exhibits deceasing tendency as the applied load is added.

Based on the artificial neural network theory, a neural network approach is proposed for the analysis of slope displacement time series, the neural network system analysis of slope displacement time series is developed, it is proved that this method is scientific and reasonable.

In this paper,in the case of upper protective layer mining of a mine for the engineering background, based on the model of semi-infinite plane body in elastic mechanics, the theoretical calculation model of verticalhorizontalshear stress of floor coal rock is established, and it is concluded that the stress expression of any point in the impact of distributed force. By introducing the rock strength index I and generalized Hooke's law, it is concluded that the discrimination criterion of guide gas fissure zone and pressure relief desorption belt of underlying coal rock with upper protective layer mining. The pressure relief scope of protection with the mining of upper protective layer is determined. Theoretical analysis shows that: the "pressure relief desorption zone" of the underlying protected coal seam that the vertical distance to the protective layer is 40m lags behind 22.2m.Through field test, the results show that the obtained pressure relief scope of protection is 26.98m,and the theoretical analysis results are basically similar.

Based on rock burst mechanism and the present research situation of control technique, pressure relief process of drilling to rock burst roadway is modeled by numerical simulation software, the contrast and analysis of stress field of surrounding rock are put up with and without pressure relief. The results of the calculation indicate that after drilling high stress area on the both sides of the roadway reduces obviously, but stress peak increases and its position is not converted into the deep areas evidently. It is the energy of the high stress area that makes the rock mass between the drillings failure, which achieves the purpose of pressure relief. Drilling diameter and space between drillings are main factors influencing pressure relief effect. The major the drilling diameter and the smaller the space between boreholes, the more complete the rock mass between the drillings failure and the better the pressure relief effect.

Displacement and its grow are critical to the stability of rock slope, in this thesis, by applying Genetic Neural Network to modeling the data obtained by monitoring, the patterns and trends of slope deformation are analyzed and predicted, and therefore supply the reliable basis for slope management.

The arrangement positions and the quantities are different for different types of cranes. In order to make suitable decision, much investigate and survey was done at preliminary stage, and we know that the flange connected gate legs and turntables, the connections between load-bearing beam and rotary column under the engine room and the connections between jib and turntable are easy to lose efficient, and their mainly failure modes are cracks. By the method of finite element, 32 sensors (including 21 welding strain FBG sensors and 11 temperature FBG sensors) were used after doing much investigate and survey and finite element modeling analysis, which are arranged in different places of a gantry crane of MQ2533, for real-time structure health monitoring. This method makes the sensor data obtained more realistically reflects the crane structural condition, which provides reliable data support for crane safety monitoring and safety evaluation. Then a software platform is developed to monitor the real-time stress. If the real-time stress exceeds the allowable stress, it issues an alarm signal to the operator.

The closely combination of Internet of Things and on-site monitoring and control technology is the development tendency of the site monitoring and control technology, especially the special equipment safety monitoring technology. EDGE technology is one way of Internet of Things technology realization. EDGE technology is a digital mobile phone technology which allows improved data transmission rates as a backward-compatible extension of GSM. It is also considered as a pre-3G (2.75G) radio technology and is part of ITU's 3G definition. It is used as one of the aims of the project which allows the operators to keep abreast of the crane operation status. Then a software platform is developed to monitor the real-time stress. A software platform is developed via a lot of preliminary work as mentioned above. The information is collected by FBG sensors and transmitted to the demodulator, and then the software calculates strain by a formula given in. Finally we acquire the real-time stress in different parts of the crane. If the real-time stress exceeds the allowable stress, it issues an alarm signal to the operator.

In order to improve the accuracy of measurement results, we should do our best to reduce the optical loss while welding FBG Sensors and adopt appropriate bonding technology. Taking simple tools and suitable approach can also achieve good result. We take three steps while welding FBG sensors, the steps are manufacture end face, welding, and heat shrinkable. Manufacturing end face of a fiber is the key step among them. It is important to adopt the sequence diagonal welding method and use a damp cloth to cool the other parts of the sensor while welding which can increase the accuracy of measurement. Use pen-made red light to check the fiber joints.

An approach by mixing laser and plasma to conduct nitriding treatment on the surface of titanium can improve the surface hardness, and the hardness of the surface in different nitriding depth is different. We wrote a program, by which we carried out Monte Carlo simulation calculation, in accordance with the model description by C language. In the calculation process, by changing laser power intensity, scanning velocity, nitrogen ion energy and angle of incidence, we got the distribution of nitrogen ions in iron under different conditions, and thus formed computer simulation diagram of titanium nitride process.

The choice of the number and location of sensors in the structure is the foundation of cranes structural health monitoring, which has major influence on the monitoring results. This paper taking a gantry crane as a SHM research object, uses optimal sensor placement based on Finite Element Method, the stress concentration points could be drawn by the FEM calculation results. This method carry out dynamic load stress analysis for the structure with virtual prototype, which make up for the lack of static analysis; compared with the type test methods, not only reduce the test cost, but also more flexible, and break through the restrictions of all types of extreme conditions. This method makes the sensor data obtained more realistically reflects the crane structure condition; provides reliable data support for crane safety monitoring and safety evaluation. The promotion of this method will provide important technical support for the development of the crane SHM.

Based on two-degrees-of-freedom (2-DOFs) quarter-car semi-active suspension model, a method for semi-active suspension control is proposed based on immune algorithm. According to this algorithm, an immune controller is designed to research and simulation for semi-active suspension control. Simulation results show that the proposed algorithm is effective，and compared with the passive suspension and fuzzy logic control (FLC) algorithm, its control capability is the best. Using immune controller, the RMS of body vertical acceleration, tire loads and suspension distortion are significantly reduced, so vehicle ride performance, handling stability are effectively improved.

The removal effect of simulation waste gas from laboratory, and the removal ability of benzene, toluene, xylene, ethanol, acetone, ethyl acetate and methane were studied in a biofilter tower. During the stable running period, the results showed that the removal efficiency of total volatile organic compounds (TVOCs) remained above 85%, when the inlet concentrations were 124~380 mg۰m-3. The removal efficiency of hydrophilic pollutants were higher than that of hydrophobic pollutants. The results proved that the biofilter tower was feasible to remove the organic waste gas from laboratory.

The properties of municipal solid waste is important to design and construction the landfill. In this paper, research the properties of municipal solid waste apply the indoor test and consulting literatures. The results showed that the density of Chongqing municipal solid waste is 430 ~610 , the average is 470 . The water content value of municipal solid waste in China is higher than foreign countries. The specific gravity of municipal solid waste in Chongqing is between 1.70~2.56. The porosity ratio of municipal solid waste in Chongqing between 1.0~4.0. The permeability order of magnitude is approximately . The properties of municipal solid waste includes density、water content、specific gravity and porosity ratio, these parameters will be used frequently when calculation and analysis[1]. And these parameters related to landfill capacity calculation、 stability evaluation、leachate and landfill gas collection system design. Compare to the test of soil engineering properties, the properties test of municipal solid waste is difficult. The reasons are that (1) At different time and area, the municipal solid waste content will present great difference. For example, if the region use coal for heating, the ash content will higher than other regions. (2) Due to the composition uniformity and fifferent bury time, the organic matter degradation is different, so it is difficult to obtain representative samples. (3) The traditional soil sampling and test methods have rules to follow, in contrary, the municipal solid waste sampling and methods haven’t accepted method.

Room temperature ionic liquid [1-butyl-3-methylimidazoliuBF4 was prepared under microwave irradiation. Platinum (Pt) nanoparticles were synthesized in the ionic liquid with ethanol as reductant. The structure and morphology of the Pt nanoparticles were characterized by SEM, FTIR and TG-DTA. The results show that the mean diameter of the nanoparticles was about 10nm and the surface was modified with the room temperature ionic liquid. The catalytic property was evaluated by hydrogenation of benzaldehyde in ethanol and the conversion reached up to 80% under hydrogen pressure.

SiC/Al co-continuous phase composites were fabricated by pressureless infiltration technology with reticulated silicon carbide porous ceramics as matrix and aluminum or magnesium as reinforcement phase. The effect of magnesium addition and holding time on the relative density, mechanical properties and macro morphology of the composites was investigated. The results showed that the porosity of SiC/Al co-continuous phase composites decreased with the increase of the holding time. The wettability of SiC and Al was improved with the addition of Mg. The hardness of SiC/Al co-continuous phase composites increased with the increase of the holding time. SiC and Al combined closely at longer holding time.

The quadratic programming problem in the standard support vector machine (SVM) algorithm has high time complexity and space complexity in solving the large-scale problems which becomes a bottleneck in the SVM applications. Ball Vector Machine (BVM) converts the quadratic programming problem of the traditional SVM into the minimum enclosed ball problem (MEB). It can indirectly get the solution of quadratic programming through solving the MEB problem which significantly reduces the time complexity and space complexity. The experiments show that when handling five large-scale and high-dimensional data sets, the BVM and standard SVM have a considerable accuracy, but the BVM has higher speed and less requirement space than standard SVM.