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Based on the analysis of the aircrafts oxygen supply performance, an new electronic oxygen supply regulator is designed. Meanwhile, the design calculation work is conducted and the structure parameters is obtained. From the results we can see that the designed oxygen regulator can satisfy the pilot’s oxygen demand under designed heights and that oxygen flow rise under different outlet pressures is not boundless as the valve opening width is increasing .Furthermore, when the valve opens to the half of its radius, the oxygen flow no longer changes as the opening width is increasing. Also, when it opens to the maximum, the peak demand under emergency can be satisfied.

Radon is a radioactive gas, high concentrations of radon in the environment can cause lung cancer, leukemia and other diseases. In this paper, indoor radon concentration in different places were measured and analyzed by using the RAD-7 radon monitor in a university and its adjacent areas. On-site measurements show that within 24 hours the indoor radon concentration versus time has certain regularity, different interior architectural decoration materials has a certain influence on the radon concentration, the radon concentrations in long confined spaces are significantly higher than those places frequently ventilated, floor height and ventilation conditions have a greater impact on the radon concentration. This research can provide a reference for future prevention and control of radon hazards.

The model of photon energy distribution in biological tissue has a very important significance in the diagnosis and treatment of biomedical area. The history and development of optical transmission and distribution in the biological tissue is outlined. The structural characteristics and optical properties of biological tissue are explained and discussed. To demonstrate the model of photon propagation in biological tissue, several methods about laser and biological tissue interaction of transmission theory are summarized and the physical meaning of the tissue optical parameters on is considered. On this basis, we simulated near infrared light distribution of the biological tissue with Monte Carlo methods and obtained meaningful results.

Reasonable number of direction finding station is examined in multi-station bearing-crossing location. Though it is believed that increasing the number of station is helpful to improve the location accuracy, In the paper, the maximum likelihood estimation (MLE) as an example. The algorithms and the location error models are given. The simulation results show that the location accuracy will be improved quickly with the increase of the number of the measuring participants, but the improvement will be sharply slowed down if too many station involved, which also boost the complexity of location.

With the increasingly serious impacts of NOx on environment, measures of controlling NOx are extremely necessary. Reburning technology has become a proven and effective method to control the emissions of NOx. In this paper, CFD software has been used to simulate the reburning process of South American coal (SAm) so as to study the effect of the reburning on the combustion in the furnace and NOx reduction. The result shows that, SAm reburning can reduce NOx emissions effectively, and removal rate of NOx reaches 50.63% with respect to the conventional combustion.

Flue gas of boiler is a kind of great potential waste heat resource. Relatively high temperature of exhaust has caused a vast waste of energy and serious environmental thermal pollutions. To make a full and reasonable use of the heat resource, a simplified single-tube heat exchanger is introduced in this paper. Dry air and wet air with different temperatures transfer heat with flue gas in the same model. And the results show that heat near the inner wall exchanges more violently than any other space in the heater. For dry air, the higher temperature of the air enters into the heater, the lower heat transfer effect of the heater. Heat exchange effect of the wet air with 0.03 mole fraction of water is more higher than that of dry air in this model.

The three-dimensional coupled explicit Reynolds Averaged Navier–Stokes (RANS) equations and the two equation shear-stress transport k-w (SST k-w) model has been employed to numerically simulate the cold flow field in a special-shaped cavity-based supersonic combustor. In a cross-section shaped rectangular, hypersonic inlet with airflow at Mach 2.0 chamber, shock structures and flow characteristics of a herringbone-shaped boss and a herringbone-shaped cavity models were discussed, respectively. The results indicate: Firstly, according to the similarities of bevel-cutting shock characteristics between the boss case and the cavity case, the boss structure can serve as an ideal alternative model for shear-layer. Secondly, the eddies within cavity are composed of herringbone-spanwise vortexes, columnar vortices in the front and main-spanwise vortexes in the rear, featuring tilting, twisting and stretching. Thirdly, the simulated bottom-flow of cavity is in good agreement with experimental result, while the reverse flow-entrainment resulting from herringbone geometry and pressure gradient. However, the herringbone-shaped cavity has a better performance in fuel-mixing.

Diffusion combustion of propane and air in a rotational combustor was simulated by three-dimensional numerical model based on FLUENT. Influence of centrifugal field on the flame shapes and temperatures were discussed under various jet angles changing in the plane perpendicular to the rotational axis. The flame is compressed when the value of jet angle θ is less 90°, otherwise, the flame is stretched when |θ|>90°. When θ

In low-temperature SCR, corn straws pyrolysis carbon (CS) was prepared as a catalyst support and activated carbon (AC) was a comparison. Manganese (7 wt.%) was loaded respectively on this two supports (Mn/AC and Mn/CS). In 50°C~300°C SCR experiment, the highest NO conversion by using CS is 36.6 Vol.% at 300°C, while AC 37.9 Vol.% at 200°C. After loaded the manganese element, NO conversion increases with the temperature. At 300°C, Mn/AC has the highest NO conversion (81.9 Vol.%), while Mn/AC is 65.3 Vol.%. The sulfur resistance performance test shows that NO conversion decreases with the increasing of SO2 concentration. In the 400ppm SO2 fuel gas at 300°C, using Mn/CS, NO conversion reduces 16.7 Vol.%, however, using Mn/AC, it reduces 22.6 Vol.%. It is promising to apply biomass pyrolysis carbon modified catalyst.

Spiral tube exchanger is one of the most important heat transfer devices among the electric water boilers. In this paper, CFD software is introduced to simulate the process of the flow of the spiral tube exchanger. Cases with different inlet velocities of the cold water have been conducted and results show that, temperature increment of the cold water reaches 38.87 K, 20.21 K and 12.12 K with the inlet velocity of the cold water set as 0.05 m/s, 0.09 m/s and 0.13 m/s respectively.

In this paper, a tube electric furnace is used to process the co-combustion of biomass and crude oil in air atmosphere, the influence of the biomass mass fraction and the temperature on NO and SO2 emissions are analysed. Research shows that with the increasing addition ratio of biomass to crude oil, the amount of NO in per unit heat reduces. This tendency is more apparent at high temperatures. Compared with crude oil, the NO emission of 20% biomass mass fraction at 1100°C is reduced by 25.8% while 19.02% at 700°C. SO2 emission in per unit heat decreases with the increasing biomass mass fraction. This tendency is more apparent at low temperatures. Compared with crude oil The generation of SO2 of 20% biomass mass fraction can reduce 91.5% at 700°C while 36.7% at 1100°C.

The revamping project of turning coal-burning boiler into gas-fired boiler for urban heat supply in Tianjin causes high vapor content in flue gas, which has great influences on the day lighting of surrounding buildings. In this paper, CFD software is introduced to simulate the distributions of NOx, SO2 and vapor in space after leaving the chimney and their impacts on surrounding buildings with the effect of the atmosphere. Result shows that flue gas discharged from the chimney with the height of 30 m has significant impacts on the surrounding buildings.

Near infrared spectroscopy is a promising technique in many scientific fields, but it is still a new measurement in sport science, of which coaches and athletes cannot make good use. In this paper we demonstrate how the real-time physiological oxygenated hemoglobin and deoxygenated hemoglobin concentration changes in the muscle can be measured noninvasively by near infrared spectroscopy and explain what the advantages of it is. The purpose is to reveal the mechanism and potential of muscle oxygen monitoring, which may play an important role in sport training.

Experiments of biomass char combustion in 10%O2/90%CO2, 21%O2/79%CO2, 10%O2/90%N2 and 21%O2/79%N2 atmospheres were performed in the fixed-bed reactor system at the temperature of 800°C-1200°C. The results show that at the same temperature, NO emission is higher in O2/N2 atmosphere than that in O2/CO2 atmosphere. The higher the O2 concentration is, the higher the NO yield is. As the temperature rises, the NO yield rises at first and then decreases at the same O2 concentration and atmosphere.

In fluid numerical simulation calculation, FLUENT is one of the most commonly used engineering software. By the way of pressure velocity coupling, FLUENT can solve the flow field, and use the finite volume method to speed up the convergence. In order to improve the calculation accuracy, FLUENT is divided into single precision and double precision to meet the need of practical engineering. In this paper, by using FLUENT numerical simulation software, combined with UDF programming, we analyze the temperature and smoke distribution when large building fire occurs. The GAMBIT software is used for the numerical modeling, and we use Tecplot software to carry out the post processing of results. Through numerical simulation, the fire temperature value reaches 1050K without wind, while with wind the temperature is 1030K, , which is consistent with the actual situation. In the absence of ventilation condition, concentration is 0.0112; under the condition of ventilation concentration is 0.0052, which is consistent with the actual situation. Therefore in the building fire safety, the first thing to consider is ventilation, which can reduce the fire temperature and concentration and security personnel safe evacuation.

Independent dedicated ventilation system is an advanced air conditioning system developed in last few years. There is little research on the design of the system at present. This paper establishes control equation of flow and temperature field based on the energy transmission theory and simulates heat pipe independent dedicated ventilation system using special flow field numerical simulation software. In pretreatment process of FLUENT, this paper uses unstructured six prisms and parallelepiped grid and encrypts grid which makes the result of calculation is more accurate. The simulation uses residual of 10-5 high precision to calculate, and obtains the residual convergence curve. Curve analysis shows that the calculation is very reliable and stable. In post-treatment process, it uses FLUENT results processing module, obtains the temperature flow pattern of heat exchanger independent dedicated ventilation system. We take one of the root canal for analysis. The result shows that the temperature in both sides of the tube is higher, and the temperature through the tube and close to the wall part is lower. It is coincide with the actual working condition of tube ventilation and heat dissipation outside the pipe. This result proves the accuracy of the numerical simulation and provides the reliable theory basis for the design of heat pipe heat exchanger independent dedicated ventilation system.

In this paper, we introduce an effective iterative method to solve the thermal linear system in HotSpot thermal floorplan, the iterative Conjugate Gradient Method is suitable to solve the traditional sparse matrix linear equations. We define a class of dummy sparse linear systems in iterative thermal floorplan algorithm, the iterative methods for linear system can be extended to apply to other iterative framework algorithm. We apply the conjugate gradient method to solve the thermal model in floorplan of VLSI physical design. The experiments' result shows that thermal floorplan using Conjugate gradient method is effective. The running time of our incremental conjugate gradient thermal solver with Jocabi Precondition is approximate 0.59 comparing with LU decomposition method.

The location of Su prince tomb of Ming dynasty followed the geomantic site selection principle in ancient times. The tombs which were surrounded with mountains and the water formed the environment of hiding the wind and gathering the water. Through to the geomantic pattern's research and the discussion of Su prince tomb geomantic site selection, this article proposed that the thought of coordinated with nature and the idea of ecological and sustainable development.

The corrosion behavior of hydrostatic extruded tube AZ80 magnesium alloy was investigated by polarization curves and electrochemical impedance spectroscopy (EIS) in simulated atmosphere. The results indicated that, the corrosion resistance of the hydrostatic extruded AZ80 magnesium alloy with uneven deformed grains and increased sub-grains were obviously weakened, with larger corrosion current density in the polarization curves and lower corrosion resistances in the electrochemical impedance spectroscopy plots. This was mainly because of the hydrostatic extrusion which made AZ80 magnesium alloy within large numbers of dislocation tangles. So the residual stress increased the electrochemical activity of magnesium alloy which reduced the corrosion resistance of magnesium alloys.

Neighbor statistic algorithm is a kind of commonly used algorithm, statistical analysis was carried out on certain analysis value through the grid in the window, to reflect the local and zone terrain feature. This paper discussed the method of parallel algorithm based on neighborhood statistics serial algorithm parses and terrain algorithm. Focus on the data partition strategy and aperture effects processing strategy. Experiments show that, the two optimization method proposed can make the parallel program neighborhood grid processing algorithms make full use of parallel computing resources, and then further enhance its parallel performance on the general parallelization.

This paper presents a capacitive humidity sensor in CMOS technology. The humidity sensor element is implemented in standard CMOS technology without any further post-processing, which results in low fabrication cost. The sensor interface employs a fully-digital architecture based on phase locked loop, which results in low pow dissipation. The proposed humidity sensor is fabricated in TSMC 0.18μm CMOS process and the chip occupies an area of 0.05mm2. The measurement result shows that the sensor value exhibits good linearity within the range of 10-90%RH and the interface circuit consumes only 1.05μW at 0.5V supply voltage.

In order to improve the dependability and security of the lever control system, we introduced the generalized predictive control (GPC) algorithm. We used MATLAB/Simulink program development tools to control the double capacity water tank. At first, we used the water tank level control device as the object and set up a mathematical model of the control system. Then we put forward the generalized predictive control algorithm based on the model. The simulation results show that the presented algorithm has a good dynamic response performance, fast-track settings, and a preferable control effect. Experimental results show that the improved methods are reasonable and practicable.

Double-tank water level control system is a nonlinear system in ship. It has long cubage delay and bad anti-jamming ability in ordinary. In order to improve the dependability and security of the lever control system, a improved generalized predictive control (JGPC) algorithm was introduced. We set up a mathematical model of control system with the water tank level control device as the object. Based on the mode, the improved generalized predictive control algorithm was put forward and introduced the parameter setting of JGPC algorithm. The simulation results show that the presented algorithm has a good dynamic response performance, fast-track settings, and a preferable control effect. Experimental results show that the improved methods are reasonable and practicable.

Huaibei Plain recently deposited silt by their causes can be divided into:1The recently deposited silt due to the divertion of Yellow River,is widely distributed in the Yellow River alluvial plain of Huaibei;2The deposited silt due to flooding of Huaihe River, mainly inFunan, Huaiyuan, as well as Wuhe near Huaihe River. Through the geological survey, exploration, and indoor and outdoor test data analysis, we had a research of Anhui Huaibei Plain recently deposited silt about its sediment characteristics, causes and distribution and Statistics of Anhui Huaibei Plain silt about the particle size composition, physical and mechanical properties;After comparison and analysis , the changing rule of soil physical and mechanical prosperties is evaluated in this paper.

The field test of high-concentration displacement is implemented in Lamadian Oilfield North West Block. The value of enhanced oil recovery in the central area is up to 20 percent or more. In order to explore the reason of good stimulation effect of high concentration polymer flooding in Lamadian Oilfield, the mechanism of high concentration polymer systems for EOR is conducted in this paper. The high concentration is characterized by the viscosity and elasticity of polymer in this article. The results showed that: the concentration of polymer with 25 million molecular weight reach to 3000mg/L, the increases value of viscoelasticity is the largest. So high-concentration polymer is defined as 3000mg/L. Compared with conventional polymer flooding, high concentration polymer has a greater ability to expand swept volume and effectiveness of wash oil.

In this paper, through analysis on characteristics of the operation of the mine fanner, According to the requirement of low speed and smooth operation and quick response for AC speed regulating system of mine fanner, a new control system that based on vector control of Fuzzy-PID was designed. The simulation model was simulated and analysised by MATLAB/SIMULINK. The result indicated that the vector control of Fuzzy-PID system can not only quickly responded to the change of the load torque but also have good speed control performance, and has reliable engineering practical value.

Expansive soil has the characteristics of strong swell-shrink, developing fissures and over consolidation. This kind of soil soaking into water, which leads to its volume expansion, strength reduction but compressibility decreasing make its engineering geology properties worsen. The distribution of expansive soil in Hefei is very wide, there are more pit accidents in Hefei district in recent years. Causing the accident is mainly due to the ignorance of the characteristics and damage of expansive soil. According to many years engaged in related working experience, this paper analyses two common types of damage in foundation pit accidents. Finally, throughout the analysis of several accidents, corresponding prevention measures and construction improvement scheme have been put forward.

Heterogeneity has been considered as a critical character of the rock structure. Fractal dimension makes it applicable to describe the complexity structure quantitatively. The evolution of rock heterogeneity has been investigated by surface fractal dimension parameter and covering projection method. The fractal behavior of meso-structure of the rock corroded by acid mine drainage was obviously observed. The fractal dimension of the rock structure was chosen to describe the heterogeneity of the rock structure attacked by Acid Mine Drainage. It observed that the fractal dimension of the rock structure increased and the rock heterogeneity became more distinctive during the process of attack.

As the structure of parallel robot is special in general mechanical and electrical systems, its forward kinematics needs to be solved by nonlinear equations. In this paper, for the issue that numerical iterative method requires complex mathematical derivation and programming, and is sensitive to the initial value, a Neuro-fuzzy system is proposed for solving forward kinematics model of parallel robot. Meanwhile, inverse kinematics is used for training database, knowledge representation ability of fuzzy theory and self-learning ability of neural network are combined to overcome the shortcomings that neural network cannot express human language and fuzzy system do not have self-learning ability. In addition, training and generation efficiency of the model can also be improved by reducing the input dimension reasonably. Simulation results have been showed that, in the premise of efficiency, accuracy of forward kinematics model using Neuro-fuzzy system is better than Newton-Raphson iterative method, and has better versatility.

Drilling samples of lunar soil is an important and indispensable part of Chinas lunar exploration project. The drill bit temperature during the drilling process is one of the key concerns for scholars, especially for the hard lunar rock drilling in vacuum environment. In this article, a fiber grating temperature measurement system integrated with vacuum drilling system is established. Experiment on simulated lunar rock in atmospheric and vacuum environments is taken out and compared.

The method of selective catalytic reduction (SCR) to removal NOx is very mature. However, its initial investment and operation cost are still high, which limits the development of SCR technology. Low temperature SCR catalysts can significantly reduce the cost. Catalyst active component and its carrier is the key to the efficiency of denitration. This paper summarizes the research progress of noble metal catalyst of low temperature SCR.

Low temperature SCR method has caused concern for the scholars in recent years. This SCR unit can be installed downstream of the desulfurization and particulate control devices, which is conducive to match the existing boiler system. It can relief the poisoning and blocking of SO2 and dust, so as to extend the life of catalyst. This paper summarizes the research progress of molecular sieve catalyst of low temperature SCR.

The method of selective catalytic reduction (SCR) is now one of the mature applications of NOx removal technology, which has the higher denitration rate, less secondary pollution and lower cost. However, the active temperature of traditional SCR catalyst is usually in the temperature range of 300-400°C. This kind of installation leads to the reduction of catalyst activity, and the shortage of working life. The development of efficient and stable performance of catalyst at low temperature has become a key point in the research of SCR.This paper reviews the research progress of carbon catalyst of low temperature SCR. In addition, the future research work is discussed.

Along with the unceasing appearance of the global environment questions, the people start to realize that the environment is very important to the humans survival. So the low-carbon ideas arise at this moment, the energy conservation and the environmental protection become the goal which the architectural industry presently needs to pursue. Then as the construction of raising architects, which is playing the very important role,because educational institution has the close relation with it. This article unified the current situation of architectural education in Lanzhou University of Technology, has analyzed some questions which exists in the architectural education, and proposed that the architectural education should unify the low-carbon ideas, has made some reform in the educational pattern, and has made the discussion to the next construction education's direction. The purpose is to raise the qualified architect who can adapt with time development, so as to fulfill effectively society responsibility of educational institution.

The relation between temperature rise of bit and drilling parameters in drilling lunar soil simulant is studied in this paper through experimentation. Since it is difficult to measure the temperature of bit in the drilling process, fiber Bragg grating temperature measuring system is developed. Then, drilling experiments were carried out in normal and-30°C low temperature lunar soil simulant. This research showed a clear correlation between temperature rise of bit, rotational speed and torque in drilling process under specific lunar soil conditions. And the relations in drilling the two lunar soil simulants have similar patterns.

Goafs formed in mine-out areas threat the underground mines owing to possibilities of rock burst and surface subsidence. This paper aims to discuss the feasibility, design and construction of waste rock backfill in abandoned stopes. Based on goafs distribution and stabilities in the White Bull Mine, rock backfill system with a total volume of 362,000 m3in 8 gobs was designed and carried out. The system included technologically and economically feasible stopes, conveying equipments of tramcars, rock transfer by electric rakes, haulage network and mining workings. Field effects showed that rock backfill was applicable to control potential hazards. With rock filling, goaf utilization rates ranged from 60% to 70%, which helped to control adjacent rock movement, eliminate rock burst and surface subsidence. Additionally, backfill construction reduced the lift and transportation costs of rocks by about 50%, which further lowered the land usage of surface dumping.

Taking into account the uncertainty in material property and component quality, a complex mechanical component such as a gear should be treated as a series system instead of a component when evaluating its reliability, since there exist many sites of equal likelihood to fail. Besides, conventional system reliability model is not applicable to such a system because of the statistical dependence among the failures of the every element (damage site). The present paper presents a model to estimate complex mechanical component reliability by incorporating order statistic of element strength into load-strength interference analysis, which can deal with multiple failure mechanisms, reflect statistical dependence among element failure events and that among different failure modes.

The interaction characteristic between lunar soil and coring drill is studied in this paper. According to the failure forms of lunar soil, the stress area is divided into two parts, central failure area and lateral failure area. The impacts of different drill parameters on cutting force are obtained by a rotary cutting model. And the process of lunar soil coring is simulated basing on a special built DEM (discrete element method) model, which accord to the special mechanical properties of lunar soil. By analyzing the simulation results, the correctness of the cutting model is proved.

The oxidation behavior of porous Cu-Ni-Cr alloys containing approximately 5,10 and 15 wt.%Cr, but with a similar Ni content of 35 wt.%, was studied at 650°C in air. The results showed that the oxidation of alloys follows linear law at initial stage and then the parabolic rate law. Continuous external scales of CuO and Cu2O formed on the alloys. Some internal oxide of were observed. In addition, with increase of Cr content, the oxidation rate decreased slightly.

A new method for reliability and sensitivity analysis of slope stability is proposed in this paper, which is based on strength reduction FEM. In this proposed method, the safety factor of slope can be calculated without assuming the shape and position of failure surface beforehand, and the randomness of physical and mechanical parameters of slope are considered in the calculation process. Meanwhile, the slopes failure probability is researched when the coefficients of variability change, and some useful conclusions are achieved.

Aiming at the difficulties to establish dynamic models of industrial robots, a novel fuzzy PID controller based on product strategy was presented. Membership degrees was determined according to position error and error change. Meanwhile, parameters of the fuzzy-PID controller would be tuned by the varied factors calculated from the membership degrees based on product strategy. Considering disturbance of friction, feedforward based on Stribeck model was introduced. Compared with traditional PID controller, experiment of manipulator demonstrates better effectiveness and robustness of the controller. The new controller keeps tracking error within 0.4%.

According to the requirement of smooth operation and accurate positioning for DC speed regulating system of mine hoist, a new speed control system that based on double closed-loop of Fuzzy-PID was designed. The best control scheme for mine hoist was also validated by simulation comparison with conventional PID control system in the MATLAB/Simulink. The result showed that the proposal was feasible and had practical value.

Research statuses of mechanical dynamics and fluid mechanics of a reciprocating compressor are reviewed respectively ,along with the presentation of coupled research for these two disciplines of a reciprocating compressor. Analyses for mechanical dynamics are focused on modal analysis and dynamic response analysis. Three methods can be adopted in dynamic response analysis,which are the combination of the formula derivation and finite element method, the combination of multi-rigid-body dynamics and finite element method , and thecombination of multi-flexible body dynamics and finite element method. Analytical models for fluid dynamics include 1-D computationalfluid dynamics model, 2-D computational fluid dynamics model and 3-D computational fluid dynamics model. In addition, limitations of researches for mechanical dynamics and fluid mechanics in a reciprocating compressor are also presented, as well as the prospect for the coupled research of two disciplines.

According to the requirement of smooth operation and accurate positioning for AC speed regulating system of mine hoist, a new control system that based on vector control of Fuzzy-PID was designed. The best control scheme for mine hoist was obtained, which was also validated by simulation comparison with conventional PID control system in the MATLAB/Simulink. The result showed that the proposal was feasible and had practical value.

The electrical capacitance tomography (ECT) was used to detect multiphase flows in pipelines, fluidization process and combustion phenomena in internal combustion engines, and so on. In the mentioned applications, none of them has equipment or vessel with inner diameter exceeding 1 meter. Nevertheless, there are some of large equipments like blast furnaces, coal bunkers and so on, need to detect its content distribution. These requirements could be met by ECT technology. But there are not any ECT systems can be used to detect content distribution of those large equipments, because the existing system can not measure the capacitance in change which was changed by content distribution. A new method of high AC voltage excitation and C/V circuits which has a higher excitation voltage about 20~50 times than the previous ac-based system, with an 8-electrodes sensor array that is amounted on a 2.5m inner diameter object constructed a High Voltage Electrical Capacitance Tomography (HVECT) system in laboratory. Image reconstruction experiments show that the HVECT is applicable to monitor the content distribution in the future.

Simulation study on nanowelding technology is important to improve nanowelding parameters, analyze the properties of welded structure, reveal the mechanism of nanowelding. In this paper, the progress of simulation study on nanowelding technology has been reviewed. The key and difficulties of this technology are proposed. The applications of molecular dynamics and quantum mechanics in nanowelding simulation study are introduced. Nanowelding technology is studied by molecular dynamics (MD) method, and the mechanism of ultrasonic nanowelding is revealed.

For current engineering of anti-slide piles, many problems exist in the calculation of landslide-thrust. Therefore, a new method based on the reliability theory combined with strength reduction FEM is introduced, and the landslide-thrust acting on anti-slide pile is researched here. In this method, the safety factor of slope can be caculated without assuming the shape and position of failure surface beforehand, the randomness of physical and mechanical parameters of slope are introduced, and the combined action of retaining structure and rock mass is considered. Meanwhile, the thrust distribution form and structural internal force can be calculated, which are also probabilistic. A case study shows that the calculation results are more reasonable and the applicability of proposed method is clearly dependable in calculating the landslide thrust.

Marine risers are key apparatus in connecting the subsea wells to the oil production platform. When the ocean current flow past a riser, the vortex shedding behind riser may induce vibration. If the frequency of vortex shedding is approaching or equal to the natural frequency of riser, the resonance will be generated. Such phenomenon leads to the potential fatigue damage of riser. Therefore, the safety and assurance of marine risers are widely arousing the interest of offshore engineering. In present paper, previous apparatus or methods in suppressing vortex-induced vibration (VIV) of risers used in marine engineering are firstly analyzed, and correspondingly the conditions in design of VIV suppressors are proposed. Based on the Bernoulli equation, the disturbance in flow around a bluff body and the relationship of vortex shedding in span-wise direction, a new method of VIV suppression is proposed. The numerical results have shown that the vibration of risers could be reduced by such disturbance.

Based on formulas of elastic mechanics, the axisymmetric problem applied to an elastic footing is analyzed. Using Hankel transform and finite difference method, the arbitrary points’ displacement and stress solutions of the axisymmetric elastic footing problem is obtained. Compared with recursive substitution method and transfer matrix method, this method is simple because it avoids complex formulas and exponential function calculation. The half space model is more flexible to simulate an actual footing. The numerical solutions are compared with Boussinesq’s Equation and results show that finite difference method is applicable to solve axisymmetric elastic footing problem. But in the application of finite difference method, there are a few factors that could cause calculation errors. Effective measures are needed to obtain exact solutions.

Based on the theory of elastic wave in saturated soils, the vertical vibration of a rigid circular footing resting on saturated sands is studied to obtain its analytical solution of dynamic compliance coefficients. Considering the role of water in the soil, the mass-spring-damping model of saturated sands is proposed to realize a practical way for engineering. And the stiffness and damping coefficients of model are calculated by reciprocity law equation. Compared with the solution of elastic half-space with the same Poisson’s ratio, the coefficients of the saturated sands are quite large. To comply with engineering practice, the approximate formula should be modified with multiplying them by factor in the Code for Dynamic Machine Foundation Design.