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In this paper,the relationship between 50% ac flashover voltage (U50) of long porcelain insulator string and ρESDD and ρNSDD was analyzed based on experimental results. It was shown that the relationship between U50 and ρESDD is the same as the one between U50 and ρNSDD, in which the U50 reduces with the increase of ρESDD by a power function, and the influences of ρESDD and ρNSDD on U50 are mutually independent. By using the least square method, the value of exponent of a and b were determined.

According to XRD, DTA and SEM detections, the hydration products of blast furnace slag based cementing material SL, SLG. were studied in different age periods. The XRD analysis of cementing material SL hydration products showed the composition of hydration products were mainly amorphous substances, few crystalline substances. Characteristic peak of ettringite, such as AFt, hadn’t been found in the spectral line of DTA, and it hadn’t been found in the figures of SEM, either, which was accordant with the conclusion that the cementing performance of SL mainly coming from gel of hydrated calcium silicate (CSH) and hydrated calcium aluminate. But the cementing performance of SLG mainly coming from Aft, CSH and AFm from hydration products analysis of different age periods.

The monitoring and fault diagnosis system for controllable pitch propeller is based on modern testing technology, fieldbus technology, monitoring and diagnosis technology, computer technology. The equipment consists of various types of sensors, CANopen bus devices, LabVIEW and computer, which can monitor the CPP’s operating parameters, including shaft system vibration, shaft speed, pitch angle, liquid level of gravity tank, pressure and temperature of hydraulic system, and the system can also alarm if three typical fault of shafting occurs.

Before commissioning, SVG first requires a separated excitation process: network voltage charges the capacitor on DC side in each H-bridge power module via the starting resistor (IGBT in all modules shall lock impulse). After charging, SVG has enough power for dynamic var compensation of the system. This paper introduces fundamental functions of the starting resistor in SVG, analyzes the influence of starting resistor selection on safe operation of the device, raises the principle of selection and conducts simulation verification by using of PSCAD.

Using STC89C58 MCU as the core, through the acceleration sensor and a humidity sensor for the monitoring the displacement of underground conditions, to simply realize real-time monitoring function of the displacement of underground. Introduces the working principle and software/hardware system design. The experimental results show that, the system has stable operation, achieved the expected goals.

Current specification, does not specify the full construction process. In practice, the majority of construction units according to their own experience, hard to get reliable assurance of construction quality. In the early development of new and the high permeability type layer-penetration oil on the basis of construction of the test section of this article relies on permeable layer, oil on high permeable layer construction process, quality testing, and control indicators complete process was studied, test construction and achieved good results.

The Smart Grid is the development trend of grid technology. For guiding the construction of smart grid scientifically, quantitative evaluation for the level of technology maturity of the Smart Grid construction is necessary. The evaluation results can be used for determining the stage of the current construction of Smart Grid and summarizing the problems which came up during the process of construction, also finding the gap between current satiation and individual goals to determine the direction and key job in next step. This paper take the characteristics and goals of domestic Smart Grid into account, build a maturity evaluation model which assess the smart grid maturity in three dimensionstime, production processes and technical features separately. By setting the primary and secondary parameter the model can be used for smart grid assessment in any time, scenes and region. The model make a comprehensive coverage of various aspects in the smart grid construction process and the results of evaluation can be analyzed from different dimension to find the short slab to guide the work in next step.

According to the test result about class insulator string of 32 units, a method of calculating 50% ac flashover voltage U50 based on radial basis function network is put forward in this paper. Inputs of the model are equivalent salt deposit density ρESDD and nonsoluble deposit density ρNSDD ,the output of the model is 50% ac flashover voltage of polluted insulator strings, the Orthogonal least squares algorithm was used to select right hide layer neurons and center vectors, and the weight from hide layer neurons to output layer neurons are determined by pseud-inverse method. The calculating result is in concordance with the test result, it is indicated that the model can give some references to access the pollution condition of external insulation.

High-pressure circuit breakers are very important and it undertakes the disconnection and connection control of high voltage transmission lines. It is one of the equipment of substation daily inspection. State of breakers are judged by open and close characters label, so a shape-prior active contour model to realize state automatic recognition of breaker images collected by inspection robot is presented in this paper. Shape-prior active contour model combines the shape information with CV model to build energy functional model, then set up initial position curve by a priori knowledge and drives the curve evolution in minimize energy functional process, the curve position is the character label contour when energy functional shows minimum. We do experiment for the algorithm on different images, demonstrate that the algorithm based on known character contour, have good segmentation results of circuit breaker in the image character recognition accuracy and applicability when the circuit breaker character is actually partial occlusion, local deformation, scale changes.

In this paper, the admissible conditions (regular, impulse-free and stable) for a class of continuous-time Takagi-Sugeno (T-S) fuzzy descriptor systems are investigated. Sufficient admissible conditions for the closed-loop systems under non-parallel distributed compensation (non-PDC) feedback are proposed. This approach is mainly based on the state space division properly to make the membership functions continuous differentiable. Moreover, in order to make good use of the systems’ structural information in rules, the provided conditions are obtained through fuzzy Lyapunov functions candidate and can be formulated in terms of dilated Linear Matrix Inequalities (LMIs). Finally, the effectiveness of the proposed approach is shown through numerical example by using the optimization toolbox.

In this paper, a revised social force model in the stairs are discussed. Considering the influence of the gravity to the pedestrians in the stairs, we improve the model by adding the gravity factor, which makes the simulation more reality. In additional, we simplify the direction model of the psychological force between pedestrians considering the narrow space of the stair, and this will refine the computational efficiency dramatically. Furthermore, we also discussed the construction of the building models for the practical simulations. The experimental results in this paper shows the valid of the model.

In order to study the influence of welding process and local detail design to the life of the metro bogie frame, this paper, in view of the tee joint, researched the superposition of residual stress and external load influence on the structure strength by the finite element simulation to establish mechanical structure and welding process co-design method. Based on the above research, the fatigue strength of the overlapping structure of welding frame socket plate and beam was improved, by the co-design of the groove angle and joint-welding sequence.

A miniaturized microstrip Wilkinson power divider is proposed in this paper. The designed power divider is miniaturized by means of using the snake-shaped structure to meet the engineering requirements. During the operation frequency band, the designed Wilkinson power divider has good performance of impedance matching at three ports and the measured return loss of each port are all less than -17dB. The isolation between two output ports is better than -20dB. The insert loss is less than 0.7dB. The designed power divider is fabricated to validate the design. The proposed power divider is measured and the simulated and measured results have a good agreement.

The pressing chamber is the heart of the screw press, it forms the drainage barrel and has to contain the operating forces of the press. As press casing is an integral part of pressing chamber, the strength of the press casing ensures normal operation of the press. The mechanical models of pressing chamber of the ZX10 type press created in MATLAB 7.0 for linear programming, and the 3D model of the press casing created in UG NX4.0 software were imported into ANSYS 9.0 software and a linear static finite element analysis was performed. The visual deflection patterns the part experiences under "real world" loading conditions were obtained so as to complete the security check of strength.

Cationic styrene-acrylate latex as surface sizing agent had been prepared with the emulsion polymerization by use of styrene, dimethylaminoethyl methacrylate, 2-ethylhexyl acrylate, modified PVA 0588 as the emulsifiers. The infrared spectrum of copolymer and particle size and physical properties were separately determined. The results indicated that the obtained copolymer emulsion was very stable, the average molecular weight of copolymer approached about 45000 and polydispersity index was 1.6. The copolymer with higher quaternization degree had smaller particle size and narrower particle distribution when initiator had the same usage. The copolymer as surface sizing agent improved the hydrophobicity of paper, the water-proofing time approached 14.7 seconds at most, the copolymer with narrow particle distribution increased 7% sizing performance than the one with wide particle distribution.

The service condition of plane thrust bearing of worm shaft in an oil screw press was analyzed. The fracture failure of the bearing rings was systematically investigated through physical-chemical test, trace inspection, fractographic appearance, and metallographic structure analysis. The results showed that a great amount of network surface cracks near bearing ring edge, some dot shaped internal oxidations and secondary crack initiation, higher hardness, as well as the network carbides and coarse quenching martensites led to the early brittle fracture of the bearing rings. The further improvements were normalizing and isothermal spheroidizing annealing can eliminate the network carbides and improve the microstructure in preheat treatment process, and quenching temperature and heating time can not be too high and long in final heat treatment. Hardness of the material is preferably 60-62 HRC.

In order to reduce the effects caused by flash, subtitles, camera movement and other factors on shot detection, the method of segmenting images using histogram is improved. The frame difference between blocks are used as characters, and the weight of the blocks are used as feature weight to do fuzzy clustering . The images are pretreated according to the characteristics such as video mutation and gradually changing border. The effect that the factors of flash, subtitles, camera movement etc have on the shot boundary detection is excluded, finally the shot boundary detection is realized. The experiment shows that , whatever the video is ,the method has relatively strong robustness.

In wireless cognitive radio networks (CRNs), user will send the sensing data to neighbors for spectrum allocation. Actually only part of data will affect the allocation result. The transmission of unused sensing data isn’t cost-efficient because it consumes a great deal of computing and network resource, especially for CRNs in which the spectrum and power resource is very precious. We propose an improving transmission availability algorithm— SkyChannel Query, which can find the non dominated channels and only transmit information of these channels. The experimental results show the advantages of our algorithm in terms of saving computing resource and improving transmission availability.

In this work, the electroless plating Ni-Cu-P on aluminium is obtained successfully by direct Ni-Cu-P plating method. The effect of bath compositions on the electroless plating rate and the properties of the electroless Ni-Cu-P deposits was studied by orthogonal test. The corrosion resistance, hardness, surface morphology and components of the coating were studied by using electrochemical workstation, digital micro-hardness SEM and EDS. The optimum bath formula obtained is 0.6g/L copper sulfate, 30g/L nickel sulfate, 35g/L sodium citrate, 25 g/L sodium hypophosphite, 20g/L acetic anhydride and right amount of self-made additive. The deposition rate, hardness and corrosion resistance are all good. The adhesion between the deposits and the matrix is better. The deposits is smooth and uniformity, smooth by SEM. The deposit contains Ni 78.90%, Cu 8.65%, P 12.46% by the analyses of energy disperse X-ray.

The free response function is the foundation of mode analysis and recognition of vibration signal, and random decrement algorithm is the commonly used classical algorithm of extracting the free response function. But under the restriction of engineering conditions, it may be impossible for long-time signal acquisition, which makes the number of sample points fail to meet the requirements of the random decrement algorithm, causing the extracted free response signals to contain strong noise and other influencing factors. Aiming at the shortcomings of the existing random decrement technique, this paper proposes an improved random decrement algorithm based on multi-secant method, which can get satisfactory free response signals with short vibration response signals to provide excellent basis of analysis for the vibration mode recognition algorithm of various time-frequency domains. Actual engineering tests confirm that the improved algorithm greatly improves the precision of extracting free response signals while basically keeping the computation speed unchanged, it has high application value.

In this work, Fe-Zn coating on copper is obtained by electroless plating. The surface mor -phologies and composition of the coatings has been investigated using scanning electronic microscope (SEM) and energy dispersive spectroscopy(EDS). Corrosion behavior of Fe-Zn coating in3.5% NaCl solution is gaved a further insight. The impedance diagram indicates that corrosion resistance of coating is better. The open circuit potential of Fe-Zn coating is at about -1V. Self-corrosion potential of Fe-Zn coating in 3.5%NaCl solution shifts in the positive direction first and then shifts from -0.622V to -0.603V with increasing heat-treated temperature, while corresponding self-corrosion current decreases at first and then. increases Corrosion resistance of coating is the best when heat-treated temperature is 300°C.

In this paper, the influence of turbulence integral scale to buffeting responses of long-span bridge is analyzed by adopting 2-D buffeting theory. One cable-stayed bridge and one suspension bridge are selected as analysis object. Buffeting responses are calculated under two different wind speeds and different size of turbulence integral scales, which range from 10m to 80m in this paper. The numerical results show that buffeting responses do not change with turbulence integral scale linearly and when turbulence integral scale increases to one value, buffeting responses reach a peak. In addition, turbulence integral scale corresponding to peak value of buffeting responses rise with growth of wind speed.

This paper based on several common wireless sensor node localization algorithms. According to the concentric localization algorithm principle, we proposed an annular localization algorithm and its improved algorithm .The algorithm uses the anchor node to do node ring through certain rules, narrows unknown nodes estimate area continually, and until finally gets the minimum area contains unknown nodes. Then taking the minimum area centroid position as unknown node’s estimate coordinates. Through the simulation of concentric localization algorithm and its improved algorithm, circular localization algorithm and its improved algorithm, can conclude that: When the proportion of anchor node increases from 5% to 10%, the positioning accuracy is obviously improved in the situation of low energy consumption.

The control of particle size and its distribution has become more and more important both in theory and in practice of emulsion polymerization field. In this study, cationic styrene-acrylate copolymer containing functional monomer was converted into water-soluble polymers by reaction with quaternising agents and acids with the free-soap emulsion polymerization method. The latex was obtained at the existence of nitrogen by the copolymerization of hydrophobic monomer styrene and 2-ethylhexyl acrylate, hydrophilic monomer dimethylaminoethyl methacrylate, modified PVA-0588 as the emulsifiers. The influences of the amount of azoisobutyronitrile initiator, the amount of dimethyl sulphate quaternising agent, reactivity ratio between monomers, charge density and pH value on the preparation process were discussed. The particle size and particle distribution was strongly affected by these factors. The results showed that the latex with narrow particle distribution and mean particle size about 100nm was obtained under redox system by adjusting 33% monomer to become precursor and dropping the rest of 67% monomer, after polymerization, N,N-dimethylamino groups were fully quaternised with dimethyl sulphate to improve the stability of the solutions. The glass temperature of polymer was 58.1°C, as pH values range of solution was 3~5, the stability and charge density of polymer emulsion could improve.

The red clay in Kunming New Airport had negative effect, such as more settlement, the differential settlement, the poor property of compactness and water content too difficult to control during construction. Therefore, there were a serial in situ tests for the red clay foundation: (1) the red clay foundation was treated by the dynamic consolidation method(DCM) with cushion and the gravel pile method, then the embankment of red clay, (2)the natural foundation of red clay was filled directly by red clay and Douposi highly weathered material as the embankment material. Their deformation and pore water pressure rules of natural red clay foundation, foundations treated by DCM and gravel pile were obtained on the condition of high embankment by monitoring of settlement, horizontal displacement and pore water pressure. Test results showed that (1)during the embankment construction period, the settlement of DCM test region was maximum, the gravel pile test region second, the natural foundation of red clay was minimum.(2) the low velocity of layered horizontal displacement indicated that the slope was stable. (3) the increasing and dissipation of pore water pressure was accordance with the embankment history. (4) because it was on the embankment construction period, the monitoring data just reflected the deformation rule in the initial stage of loading.

MR dampers are new kind of the most promising devices for structural vibration control. In this paper, an overview of the structure and working principle of shear-valve mode magnetorheological (MR) damper is given. An experimental study was carried out to test the performance characteristics of a shear-valve mode MR damper, its dynamic testing was performed on a Material Testing System (MTS) under sinusoidal and triangle excitation. Based on experimental data, the dynamic characteristics, energy dissipation and dynamic response time were analyzed. The present work lays down a foundation for MR damper application in the semi-active vibration control system.

A novel 5-Degree of Freedom PCMM (parallel coordinate measuring machine) was proposed, and its motion control system was designed. Compared with the other structural PCMMs, the structure feature of proposed PCMM was described. Then its motion control system was designed with the modularized and open architecture. The controlled scheme of hardware, which based on PC, PMAC motion control card and the precision measuring probe, was developed. The software of the motion control system was written by Visual Basic6.0 language. Finally, the process of motion control for 4-UPS-UPU PCMM was proposed. The new method above for design of motion control system is simple and effective, and may be applied to other parallel machine.