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There is a close relationship between cold ring rolling product quality and ring diameter growth rate in cold rolling process, but the technological parameters are main factors in influencing ring diameter growth. The paper used both numerical simulation and experimental verification to study the effect of the core roller speed and wide-diameter ratio on increment of ring diameter in cold rolling process of deep groove ball bearing inner ring. It is found that the core roller has greater influence on diameter growth, and the faster the feeding speed of core roller is , the greater the increment of ring diameter is. Finally, it is verified that the agreement between numerical simulation and experiments is good.

Taking Jin Chuan phyllite tunnel as the research object, and based on numerical simulation of surrounding rock graded III, IV and V, the paper studied the stress characteristics of initial support and four other representative locations such as two arch vault, arch spandrel, arch haunch, and arch foot during and after the process of construction. The paper focuses on the stress characteristics of secondary lining in different locations after stability and the change of stress in different locations of initial lining before and after the secondary lining construction.

Taking Liang Zhuang phyllite tunnel as the research object, the paper tries to analyze the variation rules of formation stress and initial support stress in the construction process based on numerical simulation of surrounding rocks grade III, IV and V, and also by using the measured data to have a better analysis of the stress state of surrounding rocks and support in the construction process, thus to grasp the rules for better construction. The result shows that the maximum compressive stress of initial support increases in the process of excavation, while the maximum formation stress is relatively stable in the process of excavation, with a slightly down trend, and whether there is a rock bolt or not, it doesnt have an obvious effect on the distribution and size of initial support stress.

As a regional metamorphic rock, the engineering properties of the phyllite are rather complex. It is common that the tunnel construction safety has tremendous difficulty due to the groundwater, the initial stress state, joints, cracks and faults and other factors, so it is necessary to find an effective construction method for the construction of phyllite tunnel. To master the regular pattern of the influence of relative factors on physical and mechanical properties of phyllite is the basis to establish an effective construction method. The paper tries to analyze the influence of water and mineral composition on physical and mechanical properties of phyllite by making relevant tests on Lu Lin tunnel, and hope to give some clue to the design and construction of phyllite tunnels.

This paper approaches the rules of curvature mode and curvature mode difference about a simply supported beam. On the basis of the theory of curvature mode, through numerical simulation analysis of simply supported beam on four conditions, the result of simply supported beam with curvature mode and curvature mode difference were obtained. The results show that for the damaged beam information with numerical simulation, the curvature mode and curvature mode difference index calculated by difference method at the unit length unevenly is with strong noise, which can even submerge the beam damage information, and for different damage index of the beam, damage information from curvature mode difference curve is stronger and effected by unit length weaker than those from curvature mode curve, and damage information from curvature mode curve and curvature mode difference curve decrease with the increasing mode order.

Since the application restrictions of JC method for hydraulic structures reliability, and the drawbacks of Monte Carlo method for large and complex hydraulic structures, this paper combines MATLAB with Monte Carlo method to analysis and calculate hydraulic structures reliability. Also, this paper puts forward the grading standards for hydraulic structures reliability. Taking a masonry gravity dam for example, using the Monte Carlo method and MATLAB programming to analysis the dam's sliding and strength failure risk, and then grading the dam. The results show that the application of MATLAB-based Monte Carlo method in hydraulic structures reliability is simple and quick, with good usability and operability.

The hydraulic fracturing method is a common method to measure the ground stress. This article describes the principles of the hydraulic fracturing method, studies the distribution and the value of the ground stress in a tunnel area with the hydraulic fracturing method, and predicts rock burst by using the Russenes discriminance and the Turchaninov discriminance. The results show that the maximum horizontal stress is between 4.7MPa and 11.1MPa, and the minimum horizontal stress is between 4.0MPa and 8.0MPa. The maximum horizontal stress direction of the drilling is between N63 °W and N72 °W, and it is not conducive to the stability of the tunnel surrounding rocks because the large angle intersection of the tunnel axis direction and the maximum horizontal stress direction.

In this paper, the peeling strength between ultra-thin copper foil and carrier is improved by some rare earths used as additives during the formation of the stripping layer of H-G alloy. The effect of different rare earth and their different contents on the stripping property of ultra-thin copper foil with carrier when they are added in the H-G plating solution is investigated, and the influence of rare earth on the cathodic polarization curves and cyclic voltammetry curves of H-G alloy during its electrodeposition is analyzed too. Results show that rare earth elements of La, Sm, Y and Ce increase the peeling strength between ultra-thin copper foil and carrier to a certain extent and the peeling strength is increased from 0.13 kgf •cm-1 to the range of 0.16 ~ 0.20 kgf •cm-1. Different rare earth contents also have impact on the peel strength and surface property of ultra-thin copper foil with a carrier support, in which the optimum adding amount of La is 0.1 g •L-1. Electrochemical test results show that the addition of rare earths can reduce the degree of the plating solution’s polarization, accelerate the electrode reaction speed, increase the alloy reduction capacity, promote alloy’s co-deposition, and improve the bonding strength between alloy layer and substrate, thus the peeling strength between ultra-thin copper foil and carrier is enhanced.

A Cartesian impedance control for a 7-DOF space robotic arm (SRA) based on the feedback from a 6-dimensional force/torque sensor on its end effecter is presented in this paper. The unavoidable position error of SRA would generate large contact forces during the connection between SRA’s end effecter (EE) and grapple fixture (GF). To control the contact force we used 6D force feedback to modify the desired trajectory controlling a PID position inner loop to make the manipulator exert desired impedance dynamic properties on its end-effecter. After optimization of impedance parameters in Simulink, this control strategy has significantly improved the force control effect in EE/GF connection experiment. Kinematic solution of the 7-DOF redundant manipulator is also provided.

Based on the theory of ANN (Artificial Neural Network),The paper raised the method of construction control, and introduced the common forecasting method. According to the characteristic of ANN itself and the complexity of factors which influence the elevation, the paper analysed the influence aspects of ANN. On the promise of bridge construction precision, the paper raised section measure、elasticity model、temperature、delay of construction and cantilever for neural network’s input vector in bridge construction process. With the help of Graphical User Interface, built ANN, made the forecast function in the bridge construction into reality. Introduce the theory of Artificial Neural Network(ANN) into long span prestressed concrete continuous rigid-frame bridge construction control.

Sea-surface wireless sensor networks (S2WSN) is a combination of many nodes forming a certain geometric shape, such as ships and sea-surface radio buoys. To satisfy the requirement of precise tracking for flying vehicle (FV) in times of exterior location datum outages, a cooperative positioning algorithm (CPA) for the FV is proposed. Time synchronization among the nodes is crucial to guarantee CPA. Taking a single-hop S2WSN as an example, the problem of low synchronization precision is resolved by two-way timing with unequal reply time (TWT-UTD). Monte Carlo simulation results show that, through optimizing the position dilution of precision among the sea-surface nodes and the FV, the absolute bias of the FV tracking by the proposed CPA is superior to that of the conventional single ship-based relative positioning method. Meanwhile, the synchronization precision is increased by more than 20% via TWT-UTD method.

To solve the precise positioning issue of underwater maneuver targets (UMTs), based on sea-surface wireless sensor networks (S2WSN) technique, this paper proposes a new positioning algorithm without exterior satellite-based or earth-based wireless navigation information as well as underwater space-time datum. The measure equations of UMT’s positioning are assembled by combining the relative radio ranges among ships with the angles of arrival from UMT. Monte Carlo simulation demonstrates that the bias of the proposed algorithm, in which the weight of heterogeneous information is adaptively adjusted by Helmert technology, is only 10% around of the conventional single platform acoustics positioning technology.

Effects of several different additions on microstructures in in-situ Mg2Si/A1-Si composites were investigated. The results show that rare earth elements have a selective modification effect on eutectic Mg2Si and Si structures. Al-Ti-B modifier should be introduced appropriately more into the composite, so as to effectively refine primary α-Al grains. As (SrCl2+RE) added increases from 0.4wt% to 2.0wt%, morphology of primary Mg2Si in a 12.0Mg2Si/A1-7.6Si composite is changed from polyhedron (or octahedron) to more irregular polyhedron with a size decrease from about 21μm to 6μm, while eutectic Mg2Si is changed from coarse dendrites to dispersed slim fibers. (RE+Al-P) can improve microstructures and tensile strength of a 7.9Mg2Si/A1-7.8Si composite; after modified by 0.8wt% (RE+Al-P), fracture surface of the composite is changed from cleavage to a mixed mode.