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This paper took flat butt joint based on Cr13 as a sample, in which TIG and MAG were adopted respectively, and analyzed qualitatively the simulation results of temperature field, stress field and deformation distribution by the finite element analysis software ANSYS. The simulating results indicate that residual transverse press stress plays a dominant role near the beginning and the end of the welding seam, that residual longitudinal pull stress is dominant in the other region of welding seam. The residual stress of MAG is higher than that of TIG. Nevertheless, the deformation of MAG is lower than that of TIG.

Damped AC (DAC) voltage method is widely used in partial discharge (PD) detection of power cable. The frequency of DAC voltage is changed due to different length of testing cable. To study the PD characteristics in the heat-shrinkable cable accessories under DAC voltage at different frequencies, four different cases of artificial defects in cross-linked polyethylene (XLPE) cables were investigated. These defects include termination without stress tube, incorrect use of insulation tape as the semi-conductive adhesive tape in the middle joint, void and metal particles on the surface of XLPE insulation. Furthermore, some characteristic PD parameters including the partial discharge inception voltage (PDIV), the partial discharge extinction voltage (PDEV), discharge magnitude, discharge times and so on were compared and analyzed. The results show that PD characteristics are different as the DAC frequency changes, which provides guidance for the practical application.

The relationship between heat treatment processes and grinding performance of cold die steel 9Mn2V had been built in this paper. Serious meshy segregation of carbide, excessive amounts of retained austenite, coarse and inhomogeneous distribution of material structure were significant causes of grinding burn and grinding crack. In order to improve the abrasion-resistance and mechanical properties of workpiece material, cryogenic and tempering treatment were added. Disappear of meshy segregation of carbide, network carbide was within second grade, retained austenite content was within 4%, martensite became much more fine and homogeneous, all of these advantages could be obtained by adopting cryogenic and tempering treatment in twice. The grinding experiment results indicated that workpiece material 9Mn2V which using this process could provide superior grinding performance.

Based on the problems of development and modernization of urban transportation in China, it introduces the fact that the widely construction of expressway over the past decade as a starting point to analyze its characteristics. Firstly, it analyzes the features of intersection and general design principles of intersection, and studies the specific design methods of intersection. Secondly, the paper studies the span arrangement of Prestressed Concrete Continuous Girder Bridge based on the structural characteristics of the bridge itself. Finally, it studies the span arrangement concerning the traffic design of intersection, and the writer designs the traffic arrangement of intersection and the span arrangement of the bridge above, which is located at the middle ring expressway, Kunshan, Jiangsu and eastern part of Jianghai expressway, Nantong, Jiangsu to give an example.

The research of this paper is based on the domestic airline operational control that exist variety of factors under the state of emergency, such as emergent meteorological conditions, flight flow and alternate airport security conditions, the potential human factors and organizational management operation, in order to establish the correct hierarchy model, we analyzing the inherent correlation of these explicit and implicit factors which impact on the dispatch release work, then apply these factors to the Bayesian network structure and use Gaussian normal distribution to solve mean value and mean square error to determine the weight for influence factors so that run a aviation safety assessment for dispatch operation, it can help the company to propose targeted security operating strategy.

Considering different kind of external grid failures, this paper gives analysis of voltage fluctuation and flicker of large petrochemical enterprise grid. Trajectory-based time-domain dynamic simulation method is used to analyze problems of transient voltage security. A strategy for the application of STATCOM is proposed in order to improving electric power quality. The total loss of motor load of the whole system is counted and buses are sorted according to sensitivity analysis to ascertain installing sites of STATCOM. Then the optimal capacity of STATCOM can be gained by the way of solving linear programming model,which is suitable for transient voltage security under multi-faults. Test simulations show very encouraging result.

The development of new energy industry is one of the important breakthroughs to solve energy and environmental issues and fulfill commitment to the international community for China. SWOT analysis was used to study the new energy industrial upgrading in Tianjin in this paper. By analyzing the strengths, weaknesses, opportunities and threats of the development of new energy industry in Tianjin, the current situations and problems were summarized, in order to provide reference for the practice of new energy industrial upgrading in Tianjin.

To study the mechanism of cascading failures in a power grid and find out the key vulnerable lines propagating cascading failures, entropy theory and analysis hierarchy process were applied in entropy-weighted fuzzy comprehensive evaluation model, and information of objective data and the subjective opinion of experts were combined in the model to implement effective evaluation and sorting of line vulnerability. The article builds a index system that contains voltage deviation, power flow coefficient and electric betweenness in considering the network structure and real-time running state of the system, and then the lines vulnerability assessment method is proposed .This method can be used to help power grid designers and operators spot the lines prone to black-out. Numerical example results show that the proposed indicators can overcome the deficiency of existing indicators not taking the state of the grid structure and operation into account which proves the assessment method is feasible.

Through the summary of typical accident, the problem between the over speed protection device of thermal power unit steam turbine and over frequency generator tripping measure is analyzed in island operation of sending ends of regional grid. The optimizing allocation principle between over frequency generator tripping measure and over speed protection equipment is put forward. By a variety of program analysis and comparison, the optimizing scheme is given. Finally, the typical models of thermal power unit steam turbine over speed protection are established in software. Based on a practical power system as an example, the whole process of islanding is simulated. Checking the coordination with existing over frequency generator tripping measure and the relay setting related to power network in the islanding operation, the validity and practicability of the optimal scheme and principle are analyzed. With the method, the regional grid will remain safe and stable.

Analyzed about the present situation of energy logistics service quality, and combined with related literature at home and abroad, select “energy logistics tracking information timeliness”, “accuracy of energy logistics tracking information”, ”energy delivery time accuracy”, “energy distribution accuracy “, “energy integrity “, “error handling” six elements as a measure factors of the energy logistics service quality, establish research model. Through questionnaire investigation and quantitative analysis verify this research model. The Conclusions: energy distribution of accuracy have significant positive effects on sustainable development, and influence degree; Energy delivery time accuracy, integrity have significant positive effects on sustainable development, but the impact is relatively small; While energy logistics tracking information timeliness, accuracy and error of energy logistics tracking information treatment had no significant influence to the sustainable development of economy and society. Energy logistics is an important part of the logistics industry, also is an important support of economic society and people's life. Improve the quality of energy logistics service, to play an important role in promoting sustainable development.

This paper deals with the aerodynamical problems of rigid flapping wing at low Reynolds numbers with emphasis on investigating the lift generation mechanism of simplified ornithopter. Theoretical analysis and Particle Image Velocimetry (PIV) were conducted to analyze and verify the lift generation conditions. The results revealed that the rigid flapping wing will generate lift under the conditions of both angle of attackαand free incoming flow velocityvwere not zero. With the wings flapped periodically, there were votexes formed, developed and shedding alternately. The calculation of curl demonstrated that the greater of flapping speed, the greater of curl. The statistic of circulation suggested that the circulation generation of flapping down was greater than that of flapping up, the circulation difference contributed to the lift generation. The difference of circulation will increase along with the angle of attackαin the circumstances of free stream velocityvand flapping speedπand flapping amplitudeΦmatched well.

Cement stabilized gravel has good characters like high strength, good stability, anti-erosion properties and better anti-fatigue property, but it is easy to produce desiccation cracks when humidity changes (caused by evaporation), resulting in reflection crack on the bituminous pavement surface, and then influences performance and the service life of the pavement. Along with the changes in traffic conditions, seme-rigid asphalt concrete pavement meet the two major challenges as early damage and heavy traffic. It has significant economic and social significance that support a method of construction and conserve of seme-rigid pavement which accommodate heavy traffic highway and has guidance and reference value in other conditions.It is analyzed by comparison between the performances of mixture with best amount of admixture which obtained by shrinkage test and mixture without admixture.

It is a typical and representative problem which coal mining has been causing serious damage in the Eastern Plains of China with high phreatic water level. Based on GIS technology, we analyzed the characters of cropland and coal resources, the results showed that the area of the overlapped areas of cropland and coal resources was 1.28 × 105km2, which accounted for 38.22% of the total arable land of the study area. Based on investigation and statistics, we investigated and forecast the farmland damage and analyzed the comprehensive treatment status in the typical region, the results showed that coal mining led to farmland subsided depth and perennial water, the recovery rate of cultivated land was between 50% and 70% in the treated area and more lower in the untreated area, the trend of arable land area continued to reduce would be hard to contain, the local governments faced unprecedented pressure on cultivated land protection.

Coal village relocation will bring local agricultural production and farmers living influence. Based on the city which has been moved eight villages, take the form of questionnaire from farming convenience condition, labor and agricultural structure adjustment, social security and other aspects, and analyzed the survey data with regression statistics. Relocate residents willing to continue to engage in agricultural production as the dependent variable, selecting 15 factors as independent variables, using SPSS software to carry on the Logit regression analysis model, finally determine Relevance between the main source of income and the field road built two factors and farmers engaged in agricultural production, the change in the transportation and large mechanical equipment also have great influence to the function.

Jining city is one of the key coal national development base.The width of land subsidence area , the depth of collapse and the difficulty of its government are all rare in the nationwide. This paper analyzed the coal mining subsided land and village relocation situation in Jining city , summarized the situation of the coal mining subsided area comprehensive governance and the coal under villages relocation and pointed out the difficulties and contradictions of these two efforts.And it also proposed that establishing a sound reduction loss mechanism of cultivated land protection, and adjusting and perfecting the land policy of coal under villages relocation are the keys to solve the above problems.

China is a country with rich coal, coal mining plays an important role in our country's energy security. But at the same time, in support of national progress of energy industry and national economic development, coal mining has caused a lot of damage to the ecological environment and social issues. The exploitation of underground resources not only leaded to the ground the destruction of arable land, but also damaged the ground coal mining under village buildings seriously. This leaded to the farmers of the coal mining under villages lost their survival, caused the contradiction between human and land and the contradiction of the cadres and the masses, causing a group petition and a series of incidents, directly affect sustainable development of the mining area. So according to the particularity of coal mining under villages, in this paper, systematic summary and analysis research of coal mining under village on recent literature ,have very important theoretical significance and social value.

In this study, numerical simulation of XCP probe was executed. The 3D Navier-Stokes equations were used as governing equations, and the finite volume method combining two-equations turbulence model was applied. The flow field of XCP Probe was analyzed, especially around the XCP Probe's head. The results show that the arc design of the XCP Probe's head plays an important role on the steady falling speed. In addition, when the radian is 27°, the resistance of the probe is smallest and a larger falling speed can be achieved; The electrodes of probe should be located in front end of a conduit which is in the middle of the probe.

Earthquake prediction is a difficult global scientific problem. As one aspect of the earthquake prediction, seismicity prediction and subsequent earthquake is also a big difficult of science problems. Analysis of the seismic sequence and the study of the main parameters (magnitude, radiation energy, apparent stress, seismic moment) and subsequent aftershocks is an important basis for prediction of seismicity and subsequent strong earthquakes. In this study, the relations between some of main shock parameters and the maximum aftershock are obtained based on association rules.

Hydraulic system has been used very widely in the modern stage system, through the hydraulic system of the stage, we can realize many function of the stage, such as lifting and revolve, and this makes the effect of the performance even better.[1] But the hydraulic stage system is relatively huge, failure is inevitable, and the causes of system failure are varied. In recent years, the casualties caused by the system are abounding. We can set up the mathematical model, to provide theoretical support for the monitoring and control system in the hydraulic system of the stage.

This paper is to evaluate the feasibility of using warm mix asphalt (WMA) technology to produce quality open graded friction course (OGFC) mixtures. In the summer of 2012, a field trial project using Sasobit-OGFC was established in the Huanhu East Road project, Changzhou city. In line with the trail field project, the performances of raveling, draindown, rutting resistance and moisture susceptibility are conducted between Sasobit-OGFC mixtures and traditional HMA-OGFC mixtures. The results indicate that the mixing temperature of Sasobit-OGFC mixtures can be reduced by 20°Cwhen compared with that of HMA-OGFC mixtures. The performances of Sasobit-WMA mixtures are no worse than these of HMA-OGFC mixtures. A wider range of paving temperature is found when adding Sasobit into OGFC mixtures, which effectively enhances the quality of pavement construction.

Warm Mix Asphalt (WMA) technology is increasingly popular in pavement construction. In the summer of 2012, a field trial project using Sasobit-WMA was established in the Huanhu East Road project, Changzhou city. In line with this trail field project, two addition ways of Sasobit were discussed to evaluate pavement performances in terms of workability, rutting resistance, low-temperature cracking and moisture susceptibility. Results identifies that the Sasobit-WMA has benefits of the workability, rutting resistance over the HMA. Although reduced anti-cracking and water stability performances occurred for the WMA, there is no significant difference between them. For Sasobit addition ways, the dry process has an easier workability and a better anti-rutting performance than those of the wet processes. Compared with the wet processes, the dry process has a slight reduction on anti-cracking and water stability performances. However, these reduction are under the control of specifications and also suitable for pavement construction.

The feeding crossbeam on the automatic aluminous-winding machine plays a supporting role in the preparation process of feeding pipe, the deformation of the feeding crossbeam have a direct impact on mechanical accuracy, it is difficult problem in model design, which is how to design a reasonable structure and make the crossbeam meets the requirements of strength and stiffness, as well achieve lightweight design. This article considers the complex force of crossbeam, and bases on the principle of virtual work and finite element theory, using ANASYS software to make a finite element model, the relation curves of the stress and the strain under the maximum load are summarized and the stress concentration area is found, The current study provides more reliable results to improve design.

The supply of construction land index is difficult in coal villages migration, especially the construction land index in urban and rural, lacking of construction land index becomes the bottleneck of village migration. In order to ruduce the pressure of the contradiction between supply and demand of land used for construction purposes. This paper combines with the actual situation of coal villages, taking Huainan as an example, starting from the connotation and significance of the policy of linking the increase in land used for urban construction with the decrease in land used for rural construction, based on the analysis of the current situation of the city construction land use, making predictions on the potentiality of village land readjustment in coal mining areas, the potentiality of the rural residential areas hook readjustment and the potentiality of linking the increase in land used for urban construction with the decrease in land used for rural construction, the results show that the overall hook potentiality is larger.

A simple frequency response model is generally used in UFLS (under-frequency load shedding) design, without considering the impact of voltage on the frequency. In fact, in the case of large active and reactive shortage power, the system will suffer from the low voltage problem by the emergence of low frequency, which easily leads a large number of motors tripping due to low voltage protection trip in the UFLS process. The influence on UFLS is compared and problems needed to solve are put forward.

As a core of the sustainable development, the ecological civilization construction is importment to realize the harmony on the process of the social and economic development between Human being and nature. By analying the status of the ecological environment destruction caused by coal mining activities in China, this paper summarizes and puts forward five modes for the land reclamation and ecological reconstruction (LRER). Simultaneously, the existing problems of the LRER are analyzed and the related necessary measures are concluded, providing the theoretical reference for future research and practice.

The gradation of asphalt mixture is a main factor on the asphalt pavement performance, and coarse aggregate skeleton is an effect of distribution in the primary factor. The article analyses the interaction among the particle sizes of coarse aggregate by VCA and CBR double controlling index of aggregate gradually filling test, and identifies the key sizes of coarse aggregate by uniform design and grey system theory, and recommends particles size range content of coarse aggregate. The results show that coarse aggregate skeleton gradation of asphalt mixture by filling test has a good correlation with VCA and CBR.

With the improvement of China's economic development and urbanization level, more and more cultivated lands are converted into construction lands;the contradiction between land demands for economic development and cultivated lands protection is becoming increasingly acute. The work of linking the increase with decrease of urban and rural construction lands becomes the important measure to solve the contradiction. This paper analyses the problems existing in pilot areas which develop the work of linking the increase with decrease of urban and rural construction lands, and puts forward solutions to those problems.

As a sewage disposal system, a biological combination system of constructed wetlands and sand filters was set up to develop the technology, to improve the disposal performance, to offer the theoretical foundation and technical parameters for realizing the standardized engineering construc- tion. The results show that: 1) The system shows certain removal efficiency to CODCr, TN, NH4-N and TP, however because of the limited space on the bank, the results are not so satisfying.2) Among the aquatic plants selected on the principle of native species, Water Celery, Canna Generalis, Iris and Ranunculus Sceleratus can grow very well.3) The revetments make the DO rise by about 5~7mg/L, of which ecological board revetment has the best re-oxygenation performance.

With constrains imposed by natural conditions, the power generated from wind power, solar power and other intermittent energy system has great randomness and volatility. Thus, the impact from the intermittent energy to the system voltage and power flow is uncertainty. In view of this problem, this paper studies the characteristics of these double random variables and correlation. By using the typical probabilistic load flow and Monte Carlo simulation method, this paper poses the probability load flow adapted to the intermittent distributed generation. Finally, taking IEEE33 distribution system for example, this paper obtains the mutual relationship between the power from the intermittent distributed generation and the probability distribution of the node voltage, current distribution of each branch.

Planetary gear reducer is one commonly gearbox used in ROV thruster. In optimization design of planetary gear reducer of ROV thruster, a lot of uncertainties affect the reliability of gear reducer. In this paper, evidence-based design optimization (EBDO) is proposed to handle the planetary gear reducer design under two types uncertainties and first-order reliability method (FORM) is used to calculate reliability of the planetary gear reducer performance functions. Finally, an engineering example is used to illustrate the proposed model to design planetary gear reducer of ROV thruster.

As an irreplaceable energy, petroleum play more and more important role in global economic development and civilization progress of human society. With the further exploration activity and development of exploration degree, it becomes more and more difficult. Under the guidance of anticlinal theory, most anticlinal reservoirs have been found and we are confronted by complicate target. However, the development of new geological theories, such as geodynamics of sedimentary basins, petroleum system, deep basin gas and hydrocarbon accumulation dynamics, lay the foundation of sustained development of exploration activity. New technique and methodology of basin analysis and modeling, description of reservoir, imagery log, supply science guarantee for sustained development of exploration activity.

At present, the construction land of replacement area in coal villages is in rather tight supply and the great shortage of construction land has made land as the toughest problem in village relocation. In order to lessen the pressure of the contradiction between supply and demand of construction land and meet the needs of normal economic and social development, this these attempts to analyze the current situation and existing problems of the traditional village migration model, and employ the new modern model of land replacement village migration to explore how it helps to revitalize the construction land index, which is of greater significance to maintain the balance between occupying and supplying. The present paper takes the coal village in a mine of Shandong Province as a case and uses the land replacement village migration model to calculate and analyze the area of the village’s new site to obtain the new conditions of construction land index balance and annual turn-over index. It is believed from the angles of land-saving, economic and ecological benefits, the land replacement village migration model can not only help the mining enterprises to get and increase the construction land index, but can enhance the sustainable development of the economic environment.

Thermoplastic vulcanizates (TPVs) based on epoxidized natural rubber (ENR) and polypropylene (PP) were prepared in an internal mixer at 180°C. The effects of curing systems (i.e., sulfur and peroxide) on morphological, rheological, thermal and mechanical properties were studied. It is found that the sulfur cured TPVs show higher tensile strength, tear strength and elongation at break than those cured with the DCP systems. The rheological analysis indicates that TPVs cured with DCP system show lower apparent shear viscosity than those with sulfur system. SEM studies show that TPVs vulcanized with DCP system exhibit smaller and finely dispersed rubber domains, which provides it higher thermal stability than sulfur cured TPVs.

The chemical products are easy to combust and explode when transported. Especially after traffic accidents, it will do more damage than other products. Taking the transportation of chemical products as research object, by summarizing cases in websites, this paper studies the spatial and temporal distribution of chemical traffic accidents in China. Based on Geographic Information System (GIS) platform, the paper compares and analyses the spatial and temporal distribution of 836 chemical traffic accidents from 2007 to 2011. This study demonstrates that the key control regions of chemical traffic accident in China are concentrated in Chongqing, Guizhou, Guangxi and Sichuan. Furthermore, the distribution and causes of chemical traffic accidents in the four provinces are conducted.

This paper presents a human health risk assessment approach based on fuzzy transport simulation (HHRA-FTS) to create the response relationships between contaminants transport and human health. Compared to the conventional methods, HHRA-FTS employs the fuzzy transport simulation to model the concentration and fate of contaminants, and takes into account different exposure pathways of pollutions in risk assessment. It has the advantage of avoiding miscalculation of results in terms of giving an interval values for the concentration of contamination by the fuzzy simulation. The HHRA-FTS approach is applied to a real-world PH-contaminated groundwater system in Pinggu County, located in northwest of Beijing, China, for demonstration studies.

Linear low-density polyethylene (LLDPE)/nano-montmorillonite (nano-MMT) composites were prepared by melting method. Mechanical test, scanning electron microscope (SEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC) and small angle light scattering (SALS) measurements were used to characterize the mechanical properties and structure of the LLDPE composite. The results indicated that the impact strength of LLDPE decreased with the increase of nano-MMT content. However, the tensile strength firstly increased and then decreased. The aggregation of nano-MMT in LLDPE happened at larger content. The spherulite size and crystallinity of LLDPE reduced with the addition of nano-MMT. Furthermore, it was found that the structure of the spherulite was destroyed by the nano-MMT. The microcrystal size of LLDPE also decreased with the increase of nano-MMT content.

The concept of dynamic directional manipulability is taken as an evaluating index of jumping performance to quest for improvement of the jumping performance of the jumping robot in view of the mechanism design. On the basis of the jumping robot mechanism model, the dynamics equation in takeoff phase is established, and the mapping relation from the joint driving torque to the acceleration of the center of mass movement is obtained. In order to optimize the jumping performance of the robot, optimal algorithm combining with the dynamic directional measure is used to optimize the mechanism parameters of the jumping robot. The optimal result demonstrates that the research on mechanism parameters optimization of jumping robot is feasible by using the theory of the dynamic directional manipulability measure

The multi researches and experiments show that the future highway traffic accident situation is shown by the highway traffic accident prediction. In the paper, support vector regression trained by genetic algorithm is presented in highway traffic accident prediction. In the method, genetic algorithm is used to train the parameters of support vector regression. Firstly, the regression function of support vector regression algorithm is introduced, and the parameters of support vector regression are optimized by genetic algorithm. The computation results between G-SVR and SVR can indicate that the prediction ability for highway traffic accidents of G-SVR is better than that of SVR absolutely.

In the present study, AA3003, AA6061 were selected as the object to investigate the mixing condition and mechanical property of the dissimilar Friction Stir Butt Welding joint. Experimental results showed the two Al alloys of the joint were interwoven together in the river shape with an obvious gradient. When ω/v was moderate, the two kinds of materials can be better mixed together and improved the mechanical property. Meanwhile the bonding was complete under all the welding conditions. The joint coefficients could all achieve more than half of those of the base material and the best was 96% (ω=1541rad/min, v=142 mm/min).

Friction stir welding (FSW) of T-joints composed by 3mm thick 6061-T4 alloy was presented and the influences of process parameters on hardness profiles and tensile strength were discussed specifically. Two low hardness zones on the skin and one low hardness zone on the stringer were found. Tensile behaviors of T-joints were examined in two directions—in skin direction and in stringer direction. It was found that the tensile strength ranged from 170~180MPa for all specimens in the skin direction. And the specimens failed in heat affected zone (HAZ) corresponding to the lowest hardness. In the stringer direction, most fractures occurred in the stringer. In all the cases, the specimens welded exhibited the best tensile strength with ω/v=1541/218 in the stringer direction. The ultimate tensile strength was equal to 83% compared to base material.

The steel truss TV tower structure, the height is 183.1 m, which is built in 1970, was corroded obviously. In order to ensure its structural safety, completely detection and security analysis have been implement. The tower is located in the top of the ridge, and hilly terrain effect was included in the whole structure analysis. Finite element analysis of bar elements was done to inspect whole structure safety. The results show, most of the members were safe, but with the height of 120 m, stress ratio of columns and diagonal braces is large than 1, and can’t meet the requirement of current codes. Additional solid finite element analysis of joint zone shows that, stress in very local area of connection plates reached to the yield stress, but they were safe enough after plastic stress redistribution. According to the results of corrosion depth test, the finite element analysis of structure after corrosion is done. After corrosion, the bearing capacity of columns almost reaches the limitation. The increase of any load or corrosion depth may lead to the failure of columns.

In this paper, the effect of the asymmetrical electric double layers of two friction surfaces on the pressure distribution in hydrodynamic lubrication regime is discussed. Based on the origin of the streaming potential, a formula to calculate the streaming potential gradient in the lubrication regime is derived. Then, the modified Reynolds equation with considering the asymmetrical electric double layers is used in the numerical analysis. The analysis results show that the asymmetrical electric double layers lead to a significant increase of the pressure when the lubricating film is very thin (below 100 nm). Overall, the larger the sum of the two zeta potentials, the larger the pressure increment is.

The contour accuracy of XY table directly driven by two linear motors was influenced by the complicated reel-time contour error model of free-form curves, uncertainty external disturbance and dynamic matching between X axis and Y axis. To establish XY table model that easily calculated and suitable for free-form curves, real-time contour error estimate method was adopted. In order to reduce uncertainty external disturbance and dynamic matching between X axis and Y axis, the iterative learning cross-coupled controller (ILCCC) was designed for current compensation on X axis and Y axis. Simulation results show that the control scheme can enhance the robustness of the system, and effectively improve the XY table of contour precision.

With inoculum sludge from a conventional activated sludge wastewater treatment plant, formation of aerobic granular sludge for simultaneous phosphorus and nitrogen removal was realized in a sequencing batch reactor by the selective pressure as a driving force. Selective pressure created by means of decreasing sedimentation time and increasing substrate loading enhanced the formation of aerobic granular sludge, which followed four consecutive stages: acclimation, granulation, growth and maturation. Under the condition that the substrate loading were increased to 500mg COD/(L•d) and 48mg NH4 +-N/(L•d), the granules were the dominant sludge forms with most of diameter about 0.5–2.0 mm, a minimal settling velocity of 0.55 cm/s and a MLSS of 6800 mg/L after 120 days operation. The granules were composed of filamentous species with varying degrees of rod- and coccal-type bacteria. Microscopic examination revealed that granules microecosystem was more stable and should be less vulnerable to the changes of mixed liquor condition.

Conventional and modified membrane bioreactors (MBRs) are effective increasingly used in small sized wastewater treatment plant. However, their widespread applications are hindered by their elevated energy consumption and the high costs of investment for the membrane modules. In this study, we investigated a modified an improved MBR system that utilized a cost effective woven fabric instead of nonwoven as the filter material in MBR modules. The woven fabric bioreactor (WFBR) system was operated in a continuous mode at HRT from 33 to 12h. Under the operational conditions of BOD loading rates from 0.12 to 0.28 kg BOD/kg MLSS /d, the WFBR system was able to reduce up 93.57% COD. The 38μm woven fabric performed well in solid-liquid separator, with an average suspended solids retention of 99.47% at MLSS of 4710~9951 mg/L. The WFBR system eliminated suction pumping by using a gravity head in the membrane filtration of the effluent over the entire operational period of 60 d.

This paper researches on sewage discharge condition along Tonghui River in Beijing. According to stationing principle and field investigation, there are 18 sewage outlets along Tonghui River and select 7 main water quality pollution indicators and sewage flow to assess the sewage outlets’ pollution distribution. By means of SPSS soft applied in principal component analysis method, paper analysis on the main pollution indicators and the main pollution contribution sewage outlets. The result shows 3 extracted principal components reflect 88.92% information of primitive variables. Then solve the formula of the 3 extracted principal components as F1, F2, F3. According to the contribution percentage of variance in table Ⅲ, the function of comprehensive evaluation expression can be deduced as F= 0.727F1+0.187F2+0.086F3. The results show that among the 18 sewage outlets, the worst pollution contribution is No.16 outlet, the 18 sewage outlets’ pollution contribution to Tonghui River is in the order of NO.16> NO.11> NO.12> NO.3> NO.8> NO.9> NO.13> NO.14> NO.17> NO.10> NO.15> NO.6> NO.18> NO.5> NO.1> NO.7> NO.4> NO.2. The assessment result is tally with the actual situation. Administrative means, technical means and management means are the effective measures to improve water quality of Tonghui River.

In this work, a study of fatigue crack propagation (FCP) behavior of friction stir welding (FSW) joints of 7075-T6 aluminum alloy was carried out. Fatigue crack growth rate curves were determined for cracks growing in different locations of the welding lines, including prefabricated crack through welding seam center, advancing side (AS), retreating side (RS), and vertical to welding seam. A computational simulation of fatigue crack propagation was conducted by AFGROW with different stress ratios R, and the effects of R on FCP rate were analyzed. Results showed that the FCP rate in RS of the Heat Affected Zone (HAZ) was the lowest and the highest was in the region vertical to the welding seam. In the low stress intensity factor range (△K) region, the FCP rate in Nugget Zone (NZ) was lower than that in AS of the HAZ, but in the high △K region, the situation was contrary. Reasons of the results were analyzed. Compared with the standard of International Institute of Welding (IIW), FCP rates in all regions were lower and it concluded nice fatigue properties of FSW 7075-T6. The simulation made in terms of crack propagation rate (da/dN) versus △K generally showed a good agreement with the measured values. The study of effects of different R on FCP rates based on AFGROW indicated that FCP rates increased with increasing R.

Aluminum-bronze/steel duplex metal has been prepared by aluminum-bronze powder whose compact oxide film was removed by dilute HCl solution before sintering. Scanning electronic microscope (SEM), energy spectrum analysis (EDS), density measurement and compression shear strength test were used to investigate the structure, composition, relative density and bond strength of aluminum-bronze/steel duplex metal. The results show: liquid phase could wet the aluminum-bronze powder washed by acid, improve sintering activity of the powder and increase bond strength of aluminum-bronze/steel interface. The relative density of sintered aluminum-bronze is 99.6%, and shear strength of aluminum-bronze/steel interface is 132.6MPa.

An automatic identification method for the cane-end of sugarcane based on digital image processing is given considering the characteristic of the cane-end of sugarcane. An image processing method with Visual C++ is used in the dynamic acquisition and jitter procedure, and identifying the cane-end automatically. The identification system of the cane-end of sugarcane consists of the image acquisition unit, the image processing unit, the identification and control unit. After the digital image of a cane-end is collected, the identification system locates the edge between the cane-end and the body of the sugarcane immediately and automatically via image processing and identification, providing the location information of the cane-end for the following mechanical cane-end cutting method. This system can massively improve the productivity of the cane-end cutting mechanism in a sugarcane harvester.

To develop the reverse transcriptase polymerase chain reaction (RT-PCR) for the detection of European brown hare syndrome virus (EBHSV), 3 specific primers and 9 overlapping oligo primers were designed to amplify a fragment of 335 nucleotides from the genome of EBHSV according to the genome sequences published in GenBank, and a 359 bp DNA fragment of the capsid protein(VP60)gene of EBHSV was synthesized in vitro by using overlap extension PCR to construct the recombinant plasmids pGM-T-EBHSV, then the RT-PCR method was described through the optimization of reaction conditions, sensitivity and specificity tests. Results showed the RT-PCR method was supplied for the detection of EBHSV with good specificity and sensitivity. The sensitivity of the RT-PCR could reach about 50 copies of cloned viral genomic fragments (pGM-T-EBHSV), and no amplifications for RHDV, Pasteurella multocida, E.coliandSalmonellafrom rabbits detection by this approach.