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The polishing process was optimized according to the polishing rate and its consistency of HE slurry with different dilution multiple on the copper wafers, it can be confirmed that: the best pressure value of HE1, HE10, HE20, HE50 type slurries was 6890Pa, the best flow rate value of the preceding three slurries was 300ml/min, the best value of the HE50 slurry was 400ml/min. Through the planarization effects of the slurries with different dilution multiple, it can be obtained that: the initial dishing and erosion heights of the samples were both 1270nm and -500nm, and the two values respectively changed to 539.3nm, -75.7nm and 796.3nm, -191.3nm after being treated by HE1 and HE10 slurries, the step height of the wafer changed from 117nm to 72nm after being treated by HE20 slurry, the step height of the wafer changed from 88nm to 71nm after being treated by HE50 slurry. It was concluded that: the HE slurry shows strong ability for step removal when the slurry is diluted by 1 times and 10 times, the HE slurry also owns high planarization ability when the slurry is diluted by 20 times and 50 times.

No.8 Bridge is the site where Yang River flows into Guanting Reservoir. It’s an important guarantee for the water safety of Guanting Reservoir that the water quality meets the standards steadily at No.8 Bridge. Based on the monitoring data from 2006 to 2013, the interannual and annual trends and correlations among DO, NH3-N and COD of Yang River were analyzed. The factors affecting DO were also discussed. The results showed that DO and COD met the fourth-class standard for surface water. NH3-N decreased year by year and its standard-reaching rate ran up to 70% since 2009. DO and COD, NH3-N was negatively correlated, but not significant, indicating that COD and NH3-N were not important factors affecting DO. DO varied along with seasons, autumn (mean 7.47mg /L) > spring (mean 7.35mg /L) > winter (mean 6.95mg /L) > summer (mean 6.35mg /L). Temperature is an important factor affecting DO. The possible impact on water environment of Guanting Reservoir caused by DO decrease should be paid special attention.

In this paper, a novel energy-efficient single-phase induction motor with three parallel-connected stator windings and two external capacitors has been proposed. By selecting the appropriate capacitors, the currents in the three windings will be approximately symmetric at rated load, thus high rated efficiency can be obtained. Based on the symmetrical component method, the condition for balanced operation is analyzed and the method for determining the requested capacitances is also obtained. The approach for calculating the steady-state performance is proposed.

The construction of wind power transmission line lagged behind the development of wind power generation, which leaded to the issue of wind curtailed and power rationing. In the wind power concentrated transmission process, using energy storage system(ESS) can relax transmission bottlenecks, and improve capability of wind power accommodation. An optimal method of using large scale ESS for relaxing wind power centralized transmission bottlenecks was presented in this paper. The comprehensive benefit was calculated by studying the relationship between wind power improved and optimization capacity configuration of ESS. Example shows that the proposed method can achieve more benefit of transmission line and more transmitted wind power than the traditional one without ESS in the same transmission line. ESS optimal power configuration is 46MW, and optimal capacity configuration is 421MWh. The decreased amount of wind curtailed is 983.6GWh with configuration ESS, saving 472100 tons of coal-fired power plans.

Plastic materials are widely used in automobile manufacturing, and they have different mechanical characteristics at high and low temperature, which has a major influence on automobile safety. This paper mainly studies the relationship between elastic modulus and yield strength of plastic materials at high and low temperature, in order to predict the elastic modulus by the yield strength. On this basis, the values of the parameter of the constitutive model will be predicted to obtain the constitutive equation. The method meeting the precision is validated by the experiments. The method decreases experimental working, and provides technical support for product development as well.

For 300 MW inner cooling turbo generator, a discrete model for cooling material flow distribution of radial ventilation cooling system has been developed. The structure optimization is studied with this model. The effect of the radial distance and the tangential distance on stator’s radial flow distribution was analyzed and optimized. The results of the simulation show that with the same inlet-outlet flow pressure the flow deviation increased as the radial distance increased but the tangential distance decreased oppositely.

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

Largely used in industry field, bearing is one of the most vulnerable components in an equipment. Owing to the complicated and nonlinear relationship between features and corresponding specific fault, it is less efficient to diagnosis the faults in tradition ways ,especially to deal with the fault of a mega machine. BP neural network whose strength is to solve the nonlinear problems makes it more precise and efficient to determine the fault of bearing. Conjugate gradient algorithm is proposed as the training method of the BP neural network. Compared with standard training method, conjugate gradient has the advantage of training speed and generalization ability, which is confirmed by the results of neural network model whose inputs are common bearing fault samples.

DC-DC converter is a kind of power conversion equipment. Electricity is the direct power for most mechanical industrial equipment currently. However, because of the diversity of mechanical industrial equipment, electricity should be transformed through power conversion equipment. This paper presents a DC-DC boost converter with PWM control method. The hardware and the structure of the core circuit is designed and the boost principle is interpreted. The detail of the configuration circuit around is described as well.

Diffusion is a key step in solar cells production. A new continuous diffusion furnace was put forward to promote productivity. However, the paddle system of continuous diffusion furnace, not same as that of traditional ones, has two paddles to handover silicon wafers. When loading silicon wafers, the paddle produces a deformation. The deflection has a significant influence on stability and efficiency. A deflection calculation method is presented as to a specific paddle in continuous diffusion furnace. The mechanical analysis and the finite element analysis are done. The test result of deformation shows that the calculation result is close to actual situation and meets the design requirements. The calculation results are valuable references in paddle system design.

Welding nuts are being used widely in automotive industry as threaded fasteners, its security and reliability requests are increasingly high. Accurate and quick detection results for surface quality can be obtained by using machine vision. Image edge detection by Canny operator has stronger acclimatization in anti-jamming and accurate edge localization. In order to suppress noise in maximum, an improved method is put forward to calculate the gradient of Canny operator, introducing Robert cross gradient in 3×3 neighborhood when calculating the gradient magnitude in finite difference method. The experimental results show that the improved Canny operator makes more effectively on the surface detection of welding nuts.

The mechanical and thermal response of elliptical head with multi-opening subjected to thermal loads, were carried out using ANSYS software. By dispersing the structure finite elements, the mechanical and fatigue behavior were discussed by APDL language following JB4732, and the result about stress evaluation and fatigue analysis are given, from the result, we can conclude that high first plus second stress and stress concentration may be formed at the intersection between center nozzle and elliptic, as well as between eccentric nozzle and elliptic. The structural discontinuity degree and temperature fluctuation has a big influence on stress concentration, as the most common, opening nozzle of a pressure vessel, the checking of dynamic and static of the structure, especially fatigue-checking are necessary.

The mechanical behavior of plastic material is dramatically sensitive to temperature. An method is proposed to predict the mechanical behavior of plastics for cars, ranging from low-temperature low temperature ≤-40°C to high temperature ≥80°C. It dominates the behavior of plastic material based on improved constitutive model in which the parameters adjusted by a series of tests under different temperatures. The method is validated with test and establishes the basis for research and development of plastic parts for automobile as well.

In order to solve the difficulty of low contrast feature extracting between labeled features and background, a new method combined the Hough transform and Canny algorithm is put forward for tensile test using the video extensometer, and a new algorithm edge detection is also obtained based on Canny an feature region tracking as well. The algorithm has proved to be a high positioning accuracy and computational efficiency in the test.

A three layer BP NN is created to design the cam. The data of cam contour ,which can be measured by CMM, has been used for the training where back propagation method is used.Advantage of solving nonliner problems gives BP netwok the ability to make out a more demand curve of cam. Taking advantage of its learning ability,NN model fits the actual cam contour gradually until the error fulfil the demand.Cam contour is ploted by Matlab,the result of which is better than cubic curve fitting,especially in the aspects of precise and velocity.

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 researches on a method for on-line fault calculation based on expert system theory. The method improves traditional method of width precedence searching, and applies to form the node impedance matrix, which not only settles loop net but also advances calculation efficiency. To convenient for fault calculation, we process and identify the basic parameters and perform equivalent of 220kV external system. Moreover inbuilt fault calculation software has been realized, which can exchange data with SCADA system on-line.

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.

Objective: To evaluate the influence of three pattern materials on the marginal fitness of Co-Cr alloy inner crown of porcelain fused to metal (PFM) endocrown. Method: Standard molar abutments mould with 90°shoulder, 6°convergens, 5.0mm occlusal-gingival height, and 15.0mm neck diameter were made of stainless steel. Three kinds of pattern materials, including Inlay wax (group A), Casting Pattern resin (group B), and Pattern Resin (group C), were used to fabricate the pattern of Co-Cr alloy inner crown of PFM endocrown. The fitness of the inner crown finished was evaluated. T test was used for statistical analysis. Results: The means of marginal gaps between inner crown and abutment shoulder made of three pattern materials were 55.9μm for group A, 37.1μm for group B, 63.1μm for group C respectively. There were statistically significance among the 3 groups (P< 0. 05). Conclusion: As a pattern material, Casting Pattern resin is suitable for fabrication of Co-Cr alloy inner crown of porcelain fused to metal endocrown.

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 tempering temperature on microstructure and mechanical properties of 35CrMnSiMo cast steel are studies in this article. Results showed that 880°C×30min 35CrMnSiMo cast steel after quenching water, hardness up to 49.6HRC, reached 39.04 J/cm2 toughness. Tempering temperature selected 200°C, 400°C and 600°C, respectively with the increase of the tempering temperature plummeting hardness and impact toughness are on the rise, but at 400°Cdecreased. Photos can be seen from your organization after quenching, which contains a lot of lath martensite, a small amount of lump some residual austenite and martensite, 200°C tempering martensite has been reduced, some of carbide precipitation into tempered martensite. Tempering of martensite quenching slats or flake, it is made of flake martensite and small ξ carbide distribution.

Objectives The aim of this study was to compare 3D accuracy of tooth image reconstruction from three kinds of CT scans using 3D superimpositional method. Methods 18 sound extracted human teeth were scanned by 3D optical system, spiral CT, micro-CT, and cone-beam CT scanner. The digital teeth images reconstructed from three kinds of CT scans were superimposed onto the standard image from optical scans respectively. Distribution patterns of shape discrepancy were presented using histogram, as well as showed in different colors on the superimposed imagines. The ratio of voluminal discrepancy versus the volume of the standard image (RVD/VS) was calculated and analyzed, using the matched-pair t-test and rank sum test. Results Compared with the standard tooth image, the average RVD/VS of digital teeth images by the micro-CT, cone-beam CT, spiral CT scans were 5.11%, 20.73%, 24.60% respectively, and there were statistically significant difference among the three kinds of CT scans (P

This paper mainly studied the high temperature quenching oil quenching, tempering temperature on the influence of high strength steel mechanical properties of wear resistant. The results show that high strength and toughness wear-resistant cast steel with 880°C× 30min after oil quenching, the hardness of 38.6HRC steel, the impact toughness value reaches 40.18J/cm2. After 200°C, 400°C and 600°C tempering, with the increase of the tempering temperature, the hardness decreased linearly, as by 600°C tempering, the hardness has been reduced to 22.3HRC. Impact toughness with the tempering temperature, the overall upward trend, the impact toughness of some reduced at 400°C, the highest impact toughness value reaches 113.34J/cm2. From the fracture morphology can be seen, with the increase of tempering temperature, ductile fracture increased, by 600°C tempering is dimple fracture, obviously can not see the traces of brittle fracture.

A secure and stable equipment management system is very important to an enterprise, the use of advanced technology in equipment management system, now the popular application of advanced distributed database operation mode, make the equipment management information system has strong practicability and high reliability. The equipment management work requirements, procurement plan, use, repair, and scrap the whole process of information recording, tracking, monitoring, both capital plan, which is the organic combination of physical and financial, and provides users with detailed and accurate information and convenient management means.

This paper proposes a kind of on-line control system for operation mode in substations, which can read data on-line from EMS, and then calculate total loss of substations in parallel operation, split operation or individual operation mode. According to the result, the system can select the most optimized way and feed the conclusion back to EMS, which can make substations operate in the most optimized way. The system is suitable for optimization of substation in rural power grid.

Trajectory planning and simulation of docking tests on the ground for space simulator is one of key technologies to complete space docking mission. A new time-optimal trajectory planning algorithm is proposed based on minimum acceleration limitation. It is realized by searching maximum acceleration to obtain the best time according to PSO (particle swarm optimization). Through calling matlab script by LabView and capturing control set points, 3D CAD model is driven to verify the rationality of the trajectory planning algorithm and model design. The simulation results show that the simulator using the proposed algorithm can move smoothly and reliably meeting the experiment requirements.

In this article, the authors use of Si, Mn, Cr as the main alloying element, developed a tough wear resistant cast 35CrMnSiMo, after casting, to obtain a wear-resistant cast steel with a hardness and impact toughness mechanical performance testing, metallurgical microscope and scanning electron microscope analysis of the microstructure. The results show that, the cast 35CrMnSiMo 850 °C austenitizing insulation 30min and then quenched, the material water hardened degrees is much larger than the oil hardened degrees. The the water hardened than oil hardened degrees up 28.5%. Metallographic photo clearly see a lot of lath martensite, the small amount of lath martensite and retained austenite, the oil quenching microstructure edge outline is somewhat vague, while clear the water quenching microstructure edge contour darker, impact toughness with hardness is inversely proportional to the sample.

This paper mainly through the experimental study on the heat treatment process and mechanical properties of cast steel 35CrMnSiMo.According to the effect of alloy elements in design of a high-toughness abrasion-resistant cast steel, Cr, Mn, Si, as the main alloy elements, supplemented by a small amount of Mo, the casting molding, for hardness and impact toughness test of mechanical properties of experimental steel. The results show that, the as-cast 35CrMnSiMo by 880 °C, quenching for 20min then, the same quenching temperature, quenching hardness of materials is far greater than the oil quenching hardness. Water quenching hardness up to 25% higher than the oil quenching hardness, The impact toughness of specimen is inversely proportional to the contrast relationship Hardness.

Columnar crystaldendriteequiaxial dendritescolumnar crystalNanosized powder was synthesized by direct-reactive precipitation process using a stoichiometrical mixture of TiCl4, BaCl2 as the reactants while NaOH as precipitant. Under the ratio of Ba to Ti is 1.02, PH=13, three reaction temperature of 70°C, 80°C and 90°C were conducted respectively. Morphology and phase structure of powder were investigated, and the influence of reaction temperature on powder morphology was discussed. The result indicates that synthesized powder is single cubic BaTiO3 and contains no impurities. BaTiO3 powders generally show spherical, and average particle size decreases with increasing reaction temperature. When reaction temperature is 80°C, BaTiO3 powder has best uniformity and dispersivity with the diameter of 80-100nm. The influence of reaction temperature on powder particle size can be attributed to the corporate contribution of nucleation and growth rate. Polyglycol as surface active agent has a significant effect in restraining agglomeration.

Nitrogen-doped TiO2 nanotubes (N-TNTs) were fabricated on the titanium foil by anodic oxidation and followed by annealing at NH3 environment. Highly ordered nanotubes, roughly 150 nm in the diameter and 20 μm in the length, were synthesized on the titanium foil. By controlling oxidation voltage, the thick TiO2 nanotubes were peeled off from the titanium substrate. In one step annealing at NH3 environment, nitrogen replaced oxygen and doped into TiO2, but anatase phase was formed.

Simple joint is a common connection in tubular structures. Local buckling occurs in panel zone when the joints bear heavy loads, and local buckling will reduce the bearing capacity and stiffness. In order to improve the bearing capacity of tubular joints, the joints need to be strengthened. In this paper, the bending performance of the joints will be enhanced by welding a tile shaped plate outside the surface of panel zone of chord member. By ANSYS finite element program, the bearing capacity of the joint with different tile shaped plate was analyzed. The results showed that the bearing capacity of the joints experience obvious change with variation of thickness, whereas the bearing capacity has no change with variation of radian.

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.

Cylindrical shells are widely used in civil engineering. Examples include cooling towers, nuclear containment vessels, metal silos and tanks for storage of bulk solids and liquids, and pressure vessels. Cylindrical shells subjected to non-uniform wind pressure display different buckling behaviours from those of cylinders under uniform external pressure. At different aspect ratios, quite complex buckling modes occur. The geometric nonlinearity may have a significant effect on the buckling behavior. This paper presents a widely study of the nonlinear buckling behavior of cylindrical shells of uniform thickness under wind loading. The finite element analyses indicate that for stocky cylinders, the nonlinear buckling modes are the circumferential compression buckling mode, which is similar to cylinders under uniform external pressure, while for cylinders in mediate length, pre-buckling ovalization of the cross-section has an important influence on the buckling strength.

This paper focuses on a new type of 8-roll cold rolling mill with the back-up bearing roll. Compared to the traditional 6-roll cold rolling mill, a thick-walled bearing roll is used to multi-support the intermediate roll. By the rack, the fan-shaped gears, the eccentric core shaft and the servo-cylinder, the work roll can be pushed down by this screw down device on the top of the mill; By contrast with the 4(6)-roll mill, this type of mill has some characteristics, such as: the small size of rolls, lighter weight, the fast response for the screw down. The bearing roll is fixed by the supporting blocks placed on the rolling-mill housing. So this mill has large traverse rigidity, and this is propitious to the flatness control. By different means of strip flatness adjustments, such as the intermediate roll shifting, the roll bending and the bearing roll adjusting, the strip flatness can be well controlled. The oil-gas lubrication is used in the bearings of the bearing rolls, and the changing rolls equipment is designed for this type of mill too. A series of this type of mills (as 450, 800, 1250, 1450 series) have been produced since it was developed in 1997. The mills for 1250 and 1450 series have been applied in five-stand cold rolling mill and single stand reversing mill, a rolling speed of 800m/min has been achieved.

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.

Based on the experiment,the forming properties of Aluminum alloy in liquid forging was studied by adding rare-earth metal Y (Yttrium) modificatior and ternary modificatior(25% NaF +62% NaCl +13% KCl).The structure and mechanical properties of the prepared samples under two modifications were compared.The results showed that the rare-earth metal Y can modificatior liquid aluminum alloy forging a comprehensive mechanical properties of a substantial increase, the use of rare-earth metal Y (Yttrium)modificatior was better than ternary modificatior.