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This paper introduces a design program for supporting of deep foundation pit through the actual example for Beijing Moisten the world Center project to solve the difficulties of high water content in foundation soil, sensitiveness to surroundings, and difficult control of quick sand and flowing mud in the process of supporting of foundation pit. This program adopts a supporting system with upper soil nailing wall and lower pre-stressed anchor pile and a comprehensive water-proof curtain (Retaining piles + Long spiral high pressure jet grouting & mixing piles) to effectively solve the above difficulties. It is indicated through actual monitoring that displacement and settlement of foundation pit meet the specification and design requirements with excellent water-proof effect. The successful application of this program provides a reference for foundation pit engineering with rich underground water, especially for engineering at hard soil layer and stratum with sand and gravel that are apt to the formation of cement-soil grouting and mixing piles, as well as engineering with limitation on dewatering of foundation pit.

Aiming at the problem that temperature filed changes can lead to edge cracks emerge to Al-Si alloy 4004 in the process of hot rolling, in this paper, finite element model of temperature field variations in the process of rolling have been established by the method of finite element numerical simulation. The relationship between temperature field variations and edge crack defects has been analyzed. The results show that temperature field of rolled piece is gradient variations, low in the center and high in the edge, metal accumulation in the edge, leading to stress concentration and forming cracks source, resulting in edge cracks arising in edge of roller piece. Finally, the reliability and accuracy of the numerical simulation method have been verified by hot-rolled tests and tensile tests. All the studies provide ideas for theoretical analysis of temperature variation during hot rolling and have important significance on improve the quality of products.

The rehabilitation robot which consists of two mechanical legs and an automatic seat was produced according to ergonomics. Each mechanical leg has three DOF. It can train patients combined with sEMG signal and FES. The rehabilitation robot has three train modes: passive mode, assistant mode and impedance mode, and it suits patients with different rehabilitation phases.

Anchoring technique has been widely used in slope engineering because of its reinforcing function to rock and soil mass. Yet the full understanding of the anchoring mechanism still lags behind the engineering practice. This paper introduces the design process and construction technology of the grouting anchor in slope reinforcement engineering. Based on bolt grouting test, it is found that the effective anchorage length of the grouting anchor depends on the size of the anchor solid and relative physical and mechanical properties of surrounding rock and soil. Research shows that the distribution of shear stress is uneven along the anchoring length. It mainly amasses within the front 1/3 part of the anchoring and increases with the development of outside load. The conclusion is helpful to describe the anchoring mechanism and instructive for engineering practice.

In this paper we study some combinatorial properties and inequalities of some classes of Z-matrices. These matrices arise in many problems in the mathematical and physical sciences. We show that all (inverse)N0-matrices are irreducible and some eigenvalue inequalities of (inverse)N0-matrices.

Widely use of composite structures such as fiber-reinforced composites advances the demand for reliable and effective techniques of ultrasonic nondestructive testing. The model to calculate acoustic field around anisotropic materials is introduced, including propagation and penetration model of Gaussian beams in front of and behind the composites. Simulation and experiments on transmitted acoustic field of composites with different thickness were conducted. Some characteristics of ultrasonic filed around composite materials, such as focal distance and beam spread have been researched theoretically and experimentally. The accuracy of the proposed model is verified by the comparison of the model-based predictions with the experimental results. The achievement will be useful for detecting the defects inside of composites nondestructively.

The interworking with the PSTN network is a network integration issues which must be solved. M2PA, M2UA and M3UA were compared and M3UA was selected because of its stronger flexibility. For the convenience of equipment expansion, IP switch was used in the hardware designation of PSTN Gateway. The software designation was based on independent entity. Socket communication mode which is loosely coupled was used between different entities. The software was divided into the SIP Proxy Module, the Signal Adapter Module, the Service Adapter Module, the Code and Decode Resource Control Module, and so on. The conversion of format, code, identification between SIP and No.7 signaling was realized. Multi-channel controller was used in the conversion of voice stream between the E1 interface circuit mode and RTP/RTCP mode. The interworking between PSTN and IMS was realized through the gateway and the old equipments can be used in the new network. This work is helpful to promote the network integration work.

Polyoxymethylene dimethyl ethers (DMMn) were synthesized in moderate yields by the reaction of methylal and paraformaldehyde catalyzed by solid acid. The pure components of DMM2, DMM3, DMM4, and DMM5 obtained by rectification were characterized by 1H NMR and mass spectra. The suitable components for blending into fuel were obtained by distillation separation. Furthermore, the combustion and emission characteristics of a diesel engine fueled with diesel and a blended fuel of DMM3-5 and diesel were investigated respectively.

In this paper, an Improved Ant Colony Algorithm is applied to the identification of the ship motion modelNomotos 1st-order nonlinear model. A robust method based on Ant Colony Algorithm is proposed for the optimization of the continuous function. The transfer criterion of the ants between each layer and global pheromone updating process are described. Some experiments results show that this method has good identification accuracy. The algorithm is feasible and effective, is of enormous significance to the system identification of ship motion.

Life and ROP of PDC bits are improved greatly when rotational impact drill assemblies (TorkBuster) are used in hard rock formations. The transient drilling processes of PDC bits combined with and without TorkBuster are simulated based on ANSYS software when drilling in densify sandstone formations. Simulated results are compared. It’s found that the torsion angle of the drill pipe is lessened greatly when torsional impact is loaded with same bit pressure and torque as that without torsional impact. Torsional impact reduces accumulated energy stored in the drill pipe, relieves stick-slip vibration and improves working conditions of PDC bits greatly.

In this paper, continuous phase modulation (CPM) with rate-compatible punctured ring convolutional codes is investigated. Some typical schemes with maximum normalized minimum squared euclidean distance (NMSED) are searched and given. The performance of bit error rate for rate-compatible punctured ring convolutional coded CPM on AWGN channel is simulated, and simulation results show that this system can provide good performance of bit error rate and variable-rate capabilities. Furthermore, simulation results also prove that the transmission efficiency increases when code rate is decreasing.

In order to achieve the target of controlling SO2emissions in fumes in a short period of time in China, it is necessary to develop a SO2on-line monitoring system (CEMS) that is suitable for China. To monitor total emissions of SO2in fumes, the concentration of SO2in the fumes and fumes flow rate must be monitored simultaneously. To monitor fumes flow rate, first we must monitor its average flow velocity, this is a major technical problem need to solve in the SO2CEMS. By means of study on velocity field constant in flue, An advanced method for monitoring average flow velocity of fume by mean of velocity field constant is presented, meanwhile an innovative device has been developed to detect velocity field constants automatically, which has resolved the technical difficulty in automated monitoring of fume average velocity in the flue. Through experiment and testing, the monitoring method researched is correct, structure of detecting device is reasonable, its monitoring results are stable and reliable.

According to the characteristics of fault vibration of rolling bearing (non-stationary signals), a method of fault diagnosis based on wavelet analysis is put forward. In the method, the signals included faulty information of rolling bearing are decomposed and reconstructed by Matlab software, and by zoom frequency spectrum analysis, the fault information composition of the rolling bearings can be extracted effectively to determine the faulty type of the rolling bearings. Based on the above, an applicable fault diagnosis system for rolling bearing with surface damage in friction pair was developed. It has been proven by practice that the diagnosis method of system is surefire and its results are stable and reliable. Through being improved and expanded，the system can be applied to collect and analyze other vibration signals.

Direct Torque Control (DTC) has an important role in current motor control. This paper focus on its torque ripple of the reference vector made, summarize a 5 levels structure and novel strategy. This strategy can generate one 5-level, sectors subdivision’s vector table and select the best vector to obtain the best effect. On this basis, combined with adapted genetic algorithm and calculate optimal parameters for the speed controller. In the end, give an example of induction motor. The results show that: the conclusion is correct, the control structure is simple, clear and perform significantly. It means that the strategy is feasibility and correct.

Pre-tension of filament is critical to the characteristics of solo-sirofil composite yarn. In this paper, solo-sirofil yarns under filament pre-tension of 5-25cN were produced by modified EJM-128K ring spinning frame. The hairiness, breaking strength, breaking work and yarn evenness were tested under standard test conditions. It’s explored that when the pre-tension of filament is 15cN, perform of solo-sirofil achieve the best level with lower hairiness, higher breaking strength and breaking work, and better yarn evenness.

An experimental device capable of producing uniform metal droplet stream and electric charging and deflecting has been developed. Uniform spherical powder of 180μm in diameter was obtained after cooling and solidification. Numerical models of heat transfer and solidification of droplets were established. The thermal history including solid fraction of droplets in uniform droplet spray process were calculated. Under the common processing conditions, the cooling rate of a droplet of 180μm diameter is of the order of 103−104°C/s. To obtain homogeneous and dense preforms, the substrate should be positioned at a distance of 1.1-1.3m from the nozzle.

Aiming at the water quality characteristics of low turbidity and low temperature of the Reservoir Water derived from Yellow River(RWDFYR), the technology of micro-flocculation direct filtration for RWDFYR was studied. The effluent index such as CODMn, UV254, TOC and turbidity was investigated under the different filtration rate conditions of 4m/h, 5m/h, 6m/h, 8m/h and 10m/h. The results show that the value of removal efficiency of turbidity reached at 98%, and the value of removal efficiency of organic matter was 40% also. In this study, the removal effect was good under the filtration rate of 6m/h. Moreover, the removal effect of different filter layers was also carried out. Finally, it concluded that the backwashing cycle of filter layer should not exceed 3days.

The aim of this paper is to construct an image recongnition system based on Gabor wavelets for infrared image. An enhanced representation of the Gabor wavelets is proposed, in which the properties of Gaussian mask in Gabor wavelets is developed to enhance the envelope function, and simultaneously the parameters of the filter based on Gabor wavelets is designed depengding on the frequency response of the training images. Some experiments including infrared image recognitions are given. The good performances are verified through using the proposed scheme in this paper.

In order to improve quality and efficiency of the overall five-axis milling for arbitrary surface impellers. In rough milling, the arbitrary surface was replaced by fitted ruled surface, the flank milling was a good method to replace the point milling. In semi-finish milling, the primal surface was replaced by piecewise ruled surfaces, using step flank milling to gain the satisfaction in model’s nicety and machining efficiency. Then , algorithm of the paper is proved to be viable by Model building, NC programming and machining.

Value of viscosity of liquid at an arbitrary velocity is important in many manufacturing processes, method of rotation is used commonly to measure it at a scheduled velocity, but it is not convenient to measure it at an arbitrary velocity. A method based on cylinder rotation is presented in the paper and it is used to measure it at an arbitrary velocity. Derivation of mathematical models is executed and a simulation is carried in Matlab. Results show that the velocity of the cylinder in the liquid attenuates by exponential law and it is in accordance with mathematical models. Error analysis indicates that that the generation of them mainly results from unsuited velocity of cylinder, slippage between the cylinder and the liquid and misalignment between the cylinder and the cup.