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A machine intelligence assistant BCI fusion navigation method of an outdoor mobile robot is put forward in view of the problem of BCI’s low signal-to-noise ratio, bad accuracy and long time delay. A vehicle navigation system based on BCI and dual laser radar is designed and implemented. First, improved angle potential field method based on dual laser radar is used for local path planning, then with navigation intention from BCI system, control commands are generated by fusion decision and used for driving a electric vehicle with modified mechanical system. Experiments show that the system can realize intelligent obstacle avoidance and human-machine collaborative navigation based on environmental obstacle information and brain machine interface control intention and it has higher accuracy, fault tolerance and robustness

Based on the theory of target curve, a method of improving flatness target curve is proposed. The transverse temperature distributions of strip are measured and described with a biquadratic expression, and the statistics method is used to analyze the temperature distributions. Finally, the additional temperature stress compensation is calculated to improve the strip shape.

In order to objectively evaluate the input-output efficiency of the construction industry in the western region, this passage analyzes the input and output status of each construction areas in the west in 2012 by establishing DEA model , and in compare with the national average. Results showed that: in 2012, the input-output efficiency of construction, the highest values in the western region is Guangxi Province, the lowest in Tibet, and the overall efficiency of the majority of the western region higher than the national average, Finally, the passage pointed out the insufficiencies about input-output of construction industry development in some western areas, and propose recommendations for improvement.

This paper deeply researches on successive action zone and dead zone of transverse differential protection in parallel lines, and improves the existing analysis software for relay protection action. First determine which zone the fault point belongs to, and then analyze the protection action according to the different zone concretely. This improvement will greatly increase the accuracy to analyze the relay protection action, and will be significant to the safe and stable operation of regional networks.

In this paper, research the hypereutectic high chromium cast iron by the methed of semi-solid method for cooling inclined plate. Influence of cooling rate on size of primary carbides and mechanical property of hypereutectic high chromium cast iron. The results showed that, speed up the cooling speed can effectively refine eutectic primary carbides in hypereutectic high chromium cast iron. The primary carbides was globularity and slug, provided with excellent mechanical properties. But when the cooling speed is too fast, the pouring temperature is too low, so that the liquid metal has high viscosity, poor mobility. there were a small amount of inclusions in the Preparation of casting. Although still generate pieces of fine carbides in the matrix, but the distribution is not uniform. disadvantage of the comprehensive performance.

This paper applies the theory of expert system to analysis for relay protection action based on PAS. And it also summarizes various rules according to the experience of operating personals and relay protection personals for several years. All these rules are suitable for 110kV and 66kV regional networks. This paper not only analyzes three-phase current protection, zero-sequence current protection, distance protection etc, but also discusses some special situations such as under voltage lockout over-current protection for transformer, remote backup protection etc.

By analyzing the two lightning accidents happening to a 500kV substation situated in the lightning-prone northeastern Guangdong Province, I conclude as follows, there should be some problem in the equipotential earthing of the secondary system of this substation. Specifically, the existing potential difference in the secondary equipment gave rise to the meltdown of it which finally caused the accident. In the context,I build the one-point earthing parallel system simulation model according to ATP graphic pretreatment program, then by using slope-ramp simulation I study the lightning current which leaked into the grounding grids of the substation.In conclusion, the application of high frequency signal mixed low frequency signal earth system in the secondary system and the equipotential bonding is key to preventing accidents.

In this paper, the transient characteristics of the permanent magnet synchronous motor based on the space vector pulse width modulation technology are researched in detail. Firstly, the mathematical model of the control system is established. Secondly, the simulation model based on MATLAB/Simulink is built. Thirdly, the transient simulation is implemented by the constructed model. It is proved that the mathematical model is valid and effective, which provides a theoretic base for the design of an actual permanent magnet synchronous motor control system.

The aim of this study is to investigate the effect of SiC particle pretreatment, aluminum matrix particle size and sintering temperature on relative density, hardness, microstructure and wear resistance to SiC particle einforced aluminum matrix composites. To this end, the amount of 16.7 wt.% SiC with average particle sizes 20μm was used along with pure aluminum of average particle size of 75 μm and 25μm. Powder metallurgy is a method used in the fabrication of this composite in which the powders were mixed using a planetary ball mill. By analyzing SEM micrograph and the Property test, it is concluded that SiC particle pretreatment has significant effect on the morphology of pecimens. pretreatment increase the interface adhesion, improve the wettability. SiC is uniformly distributed in the matrix, with good relation to the substrate, the maximum hardness is 51.1HB, the minimum wear rate is 0.1684%, while the density is 97.3%.For the same SiC content and particle size, the smaller the particle size of aluminum matrix is, the higher wear resistance of composite materials is on condition that others are same, the higher sintering temperature and the higher the wearability of composites, the wear resistance of the composite material is significantly improved after SiC pre-processing.The relative density increases with increasing aluminum matrix particle sizes under the same pressure and the holding time. The actual density of all samples reached the theoretical density over 96%, to a maximum of 98.9%.

Affordable housing is an important part of China's housing security system. This policy is adapted to the actual situation of our country. The core advantage of the affordable housing is prices. It is to ensure the healthy development of affordable housing and a premise for the real role. How to make affordable housing for protection of the population can not only afford but also comfortable stay, developed pricing is the most important issue of its construction, it relates to the different interests of the class, a scientific and reasonable to take into account the different interests sectors of the pricing model. It helps to achieve social stability, improve the construction, regulatory and pricing mechanisms of affordable housing, and has a theoretical and practical significance.

The current two-dimensional (2-D) parameters for surface assessment (Ra and Pc) could not actually reflect functional properties of bearing and lubricant retention capabilities of steel sheets and rolls surface. Based on ARM9 development board, this paper has been working on secondary development of M1 mobile surface roughness meter, creating a model of calculating three-dimensional (3-D) functional characteristic parameters with 2-D profiles, and optimizing influence factors with Genetic Algorithms (GA). By comparing with measurement results by white-light interfering profile meter, the measurement error of the developed system is within10%, which was proved to be practical in the factory.

This paper presents the data fusion survivability analysis model of wireless sensor network (WSN) based on stochastic Petri net (SPN). First, the definition of data fusion survivability is put forward, and the data fusion model of WSN is constructed. Second, the SPN modeling method of security events, which influences the WSN, is described. Lastly, simulation experiment proves the correctness and effectiveness of the modeling of WSN data fusion survivability analysis based on SPN. This model can provide the theoretical basis and guide for designing a survivable WSN.

mi-rigid base on crack resistance, using orthogonal experimental design method, arranged 16 groups of orthogonal test and conducted the water content test and drying shrinkage test that aimed at various ages from 5d to 50d respectively. The results indicated that with the increasing of waste asphalt content, the shrinkage gradually increasing and the maximum reached when the dosage of waste asphalt concrete was 55%, since then, with the increasing of waste asphalt content, the shrinkage gradually decreasing and the range was largely. Fiber has little effect on moisture loss and shrinkage, with the increasing of fiber content, the moisture loss of materials with different ages increased gradually and the maximum loss rate reached when the dosage of fiber was 4, then the moisture loss decreased gradually after that. As for shrinkage, it reached minimum value when the dosage of fiber was 2.5. Mixing waste asphalt concrete and fiber in reasonable dosage can improve the crack resistance of materials.

the control strategy has a direct impact on the performance of active power filter. Creating system model in the simulation software to research and analyze. Results show that the hysteresis comparison control method can track the harmonic current accurately, and control inverter circuit generate compensation current quickly and accurately. And doing spectrum analysis for the power grid currents before, the spectrum figures show that the power grid current harmonics has been suppressed greatly, and the compensation effect is very significant.

Simple joint is a common connection type in tubular structures. In this joint, one or more tubes are welded directly on the surface of another tube. Local buckling occurs in panel zone when the joint load is heavy, and such local buckling will reduce the bearing capacity and stiffness of the joint. In order to improve bearing capacity of tubular joints, the joint needs to be strengthened. In this paper, the bending performance of the joint will be enhanced by welding two annular plates inside the surface of panel zone of chord member. By ANSYS finite element program, the bearing capacity of the joint with different inner annular plate was analyzed, including design bearing capacity and ultimate bearing capacity. The results showed that comparing to annular plate thickness variation, the width variation and interval variation have much more influence on the bearing capacity of the joint.

Objective To assess the three dimensional (3D) accuracy of deciduous tooth surface model reconstruction from cone-beam CT(CBCT) scans using image superimposition method. Methods 14 sound extracted human deciduous teeth were scanned by micro-CT and CBCT scanner. The digital tooth models reconstructed from CBCT scans were superimposed onto the standard model from micro-CT scans respectively. Distribution patterns of shape discrepancy were presented using histogram, as well as shown in different colors on the superimposed images. The voluminal discrepancy versus the volume of the standard image (RVD/VS) were calculated and analyzed, using t test. Results There was no statistically significant difference between deciduous anterior teeth and molars(P>0.05). The mean RVD/VS of digital tooth images obtained by CBCT scans was 3.932±4.038%, and significant difference were found (P

To decrease short-circuit current, adjusting the power network operation by breaking transmission lines is the most economic and convenient measure. For large power grid, breaking transmission lines has thousands of combinations, so it's very difficult to find the best combination in a short time. Firstly, this paper formulated the sensitivity relationship between transmission line outage and impedance change. Then preliminary combinations schemes of transmission line outage were selected according to the sensitivity. Index values of factors were given using the fuzzy control evaluation. Finally, this paper determined optimal scheme from maximum priority and accomplished the accessorial intelligent optimize system of limiting short-circuit current. The rapidity and rapidity of the proposed control strategy was verified by calculating the actual power grid.

The existing research on flange focused on bearing capacity, and there were few reports on the rigidity of flange. In this paper, rigidity test was carried on for the connection of rigid flange and flexible flange in power-transformed frames. According to the test results, the axial rigidity, shear rigidity and flexural rigidity was compared. The results indicated that the axial rigidity, shear rigidity and flexural rigidity of flexible flange connection was lower than those of rigid flange connection for both the plain bolt and high strength bolt.

Test items include compressive strength, anti-breaking strength and split strength of standard concrete, rubber concrete and fiber-rubber concrete, and 43 groups test were conducted. In order to investigate the influence of the synergistic reaction between fiber and rubber powder on force-bearing performance of concrete used in subgrade, and different blended ratio effect on strength and extension of concrete were studied. The results indicated that with the increasing of content of 40 mesh rubber powder, the compressive strength of concrete decreasing regularly; with adding the blends of fiber and rubber powder, the anti-breaking strength and extension of concrete were promoted, as to fiber - 40 mesh rubber powder concrete, the content of rubber control less than 6%, and the fiber less than 0.5%，as to 60 mesh rubber powder -10mm fiber concrete, the content of rubber control less than 6%, and the fiber less than 0.5%; as to 60 mesh rubber powder -20mm fiber concrete, the appropriate adding quantity of rubber less than 2%, and the fiber less than 0.5%.

Four different types of full-scale slotted end plate (SEP) connection joints are tested to determine their failure modes and damage mechanisms under ultimate load, also analyze their force-displacement behaviors and developing processes of deformation and stress. The results show that ultimate bearing capacity of the I-type SEP joint is only approximate 1/2 of the other three types of SEP joints, which indicate the SEP’s type have great influence on the ultimate strength of joints. The instability of SEP is the main factor to cause the loss of bearing capacity of the connection joints, which is shown through the development of stress, that SEP enters into plastic stage and the other regions still are elastic.

In this paper, the 35 tons steel coil overturning machine is used in metallurgy industry. Its own weight is very great, the weight of the steel coil is also very great, whether can realize the smooth movement is a very crucial problem .By using COSMOSMotion to simulate and analyse the movement function of overturning machine, some graphics can be obtained. Through graphics some Performance parameters can be collected. Motion analysis promotes the reliability of the design also provide extremely important design parameters for the design of the overturning machine. So COSMOS Motion can provide the theoretical foundation for the product design.

Flange connection has been applied widely, and many researches have been done on flange connection both at home and abroad. But the existing research on flange focused on bearing capacity, and there were few reports on the rigidity of flange. In this paper, rigidity test was carried on for the connection of rigid flange and flexible flange in substation frameworks. According to the test results, the tensile rigidity, shear rigidity and flexural rigidity was compared. The results indicated that the tensile rigidity, shear rigidity and flexural rigidity of flexible flange connection was lower than those of rigid flange connection with high strength bolts.

The partial high points, always appearing when the hot strip is being rolled, not only negatively influence the quality of the hot strip, but also make a long term effect on the profile control. Via quantifying and separating the partial high points and analyzing the calculation of the strip crown, we can obtain the calculation method of the error resulted from the high points; then, on the basis of the way that the high points affect the profile and flatness control system, we can present some tactics to lessen the high points’ effect.

As typical shallow lake of the north China plain, Baiyangdian plays an important role on water system composition and water amount adjustment. Its water storage and average annual rainfall of the basin does not exist directly relation and its maintenance of function water amount can only rely on unconventional water supplies and diversion support. The lack of natural entering water and frequent artificially diversion makes Baiyangdian gradually become "artificial lakes". In order to solve the current problems of Baiyangdian, the control of development indexes for Baiyangdian basin water resources urgently needs to be intensified, and water diversion mechanism of basin water amount based on Water subsidise cycle should be established.