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Purpose– The purpose of this paper is to build a transient wear prediction model of surface topography of textured work roll, and then to investigate the wear performance of different original textured surfaces. The surface topography of steel sheets is one of the most important surface quality indexes, which is inherited from the textured work rolls in cold rolling. Surface topography of work roll is obviously changing in the cold rolling process. However, surface topography is difficult to measure in the industry production process.Design/methodology/approach– This paper presents a numerical approach to simulate the wear process based on the mixed lubrication model of cold rolling interface developed by Wilson and Sheu (Sheu and Wilson, 1994). It is assumed that wear takes place at locations where the surfaces are in direct contact, and the volume is removed by an abrasive particle which is an abstract concept based on the wear phenomenon of textured work roll. At each simulation cycle, the distribution of the contact pressure is calculated by the lubrication model. The material is removed by an abstract abrasive particle and the surface topography is modified correspondingly. The renewed surface topography is then used for the next cycle.Findings– Through comparative analysis, it can be found that the simulation results possess similar statistical characteristic with the measured data. A set of roughness parameters such as the amplitude, spacing and frequency-domain characteristics are introduced to analyze the wear performance of different textured surfaces. Numerical examples show that the surface topography has a significant effect on the wear performance of work roll in cold rolling.Originality/value– The proposed model can accurately predict the wear process of the surface topography in the cold rolling process, which provides the foundation for optimization of original surface topography of textured work roll. The model can also be considered as a tool applicable for research on control of the surface topography of steel strip in the cold rolling process.

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.

Anode electrogenic bacteria (AEB) widely exist in paddy soils and play an important role in element biogeochemical cycling. However, little information is available on the role of soil characteristics in shaping AEB community. Therefore, the objective of this study was to evaluate the role of soil properties in driving the evolution of anode bacterial communities. Microbial fuel cells (MFCs) were constructed for five paddy soils with different chemical properties. The bacterial communities at anodes of closed (MFC running) and open (control) circuit MFCs were characterized using 16S rRNA gene-based Illumina sequencing. Paddy soils with higher dissolved organic carbon (DOC) and ammonium (NH4 +) concentrations in porewater showed higher MFC performance. Without MFC running, the dominant bacterial community composition was similar among the used five soils with Clostridia as the dominant bacteria at class level. Compared to control treatments, MFC running significantly decreased bacterial diversity and altered the bacterial community composition at anodes. However, the shift of bacterial communities varied with different types of soils. Betaproteobacteria was enriched by 4–30 times after MFC running for low MFC performance soils, while Deltaproteobacteria enriched (4–20 times) for high MFC performance soils. Redundancy analysis (RDA) indicated that DOC, NH4 +, and dissolved ferrous (Fe2+) significantly shift anode bacterial communities for the five soils with MFC running. We found that high-performing MFCs constructed from paddy soils with high DOC and NH4 + concentrations in porewater selected for an active, highly electrogenic bacterial community (dominated by Deltaproteobacteria) at anodes, while the dominant bacterial community for the low-performing MFCs from soils with low DOC and NH4 + was Betaproteobacteria. These findings imply that soil properties shape the AEB composition, therefore influencing MFC performance. This study provides new insights into the microbial-mediated carbon and nitrogen cycling in paddy soils.

A simple and efficient strategy for the synthesis of novel aryloxy-functionalised 4,4′-bi-1,2,4-triazoles was successfully explored by nucleophilic aromatic substitution of tetrachloro-4,4′-bi-1,2,4-triazole by various phenols using Cs2CO3 as catalyst. The syntheses were achieved in 25–94% yields.

Summary extract of heterogeneous multimedia documents is an important content and requirement of information management at the Internet era. Though some summary extract approaches have been proposed in recent years, in general they can only be used in a single-type media. More important is that the existed approaches of multimedia summary extract had no satisfactory effects, and can’t be brought into practice. Aiming at these problems, an approach based on folksonomy with incentive and quality assurance mechanisms is put forward. The proven folksonomy ensures the practicality of the approach, the incentive and quality assurance mechanisms avoid the innate problems of folksonomy: cold boot and inaccurate tagging. The experiment shows that the approach is reasonable and effective.

Previous studies have demonstratedf that heat stress can induce injury of the central nervous system and lead to neuronal cell apoptosis. However, the molecular mechanisms underlying these cellular changes remain unclear. In the present study, flow cytometry was used to investigate heat-stress-induced apoptosis, and caspase-3 activation was also assessed in neurons. The role of reactive oxygen species (ROS) accumulation in the heat-stress-induced apoptosis of neurons was demonstrated using the antioxidant drug manganese (III) tetrakis (4-benzoic acid)porphyrin. The present study presents evidence that heat stress induces mitogen-activated protein kinase (MAPK) activation in rat malignant glioma F98 cells. Following the inhibition of different MAPKs with a range of specific inhibitors, SB203580 (an inhibitor of p38 MAPK), but not PD98059 (an inhibitor of extracellular signal-regulated kinases) or SP600125 (an inhibitor of c-Jun N-terminal kinases), diminished the production of ROS and apoptosis, and prevented activation of the p38-downstream kinase MAPK-activated protein kinase 2 (MK2) in neurons. Inhibiting MK2 with dominant negative adenoviral constructs or a specific inhibitor significantly decreased normal and heat-stress-induced ROS accumulation and cell apoptosis, whereas inhibition of another kinase downstream of p38 MAPK, MAPK-activated protein kinase 5, by transfection with another adenoviral construct did not exert the same effects. Taken together, these findings indicate that heat stress stimulation induces p38-MK2 pathway activation, which exerts a pro-apoptotic effect by regulating ROS accumulation in neurons.

To determine the effects of dietary constituents on soil Pb oral bioavailability, Pb relative bioavailability (RBA) in 3 soils contaminated by zinc smelting (ZS), wire-rope production (WR), and metal mining (MM) was measured under fasted and fed states with 9 foods. Under fasted state, Pb-RBA was 84.4 ± 10.3, 82.6 ± 4.70, and 32.3 ± 1.10% for ZS, WR, and MM soils; however, it decreased by 1.3-3.5 fold to 23.9-58.8, 25.6-49.9, and 14.8-24.2% under fed states with foods excluding Pb-RBA with egg in WR soil (97.3 ± 4.46%), and with cabbage and egg in MM soil (40.0 ± 8.62 and 44.4 ± 0.96%). In the presence of foods, egg and pork with significantly higher protein and fat contents leaded to the highest soil Pb-RBA (44.4-97.3%), while Pb-RBA determined with mineral-rich mouse feed was 1.6-7.9 fold lower (9.41-13.5%), suggesting high fat and protein foods tended to increase soil Pb-RBA, while high mineral diets decreased soil Pb-RBA. The increased Pb-RBA of MM soil with cabbage compared to fasted state was due to high organic content in cabbage, which could increase soil Pb solubility by inhibiting Fe and Pb co-precipitation in the intestine. For accurate assessment of health risks of contaminated soils, dietary influence on soil Pb-RBA should be considered. Refereed/Peer-reviewed

To determine the effectiveness of mineral dietary supplements to modulate cadmium (Cd) exposure, an in vivo mouse bioassay was conducted to determine Cd relative bioavailability (Cd-RBA) in Cd-contaminated rice (0.80 mg Cd kg(-1)) with and without Zn, Fe, or Ca supplements as nitrate or chloride salts. Without mineral supplements, Cd-RBA was 43 +/- 5.3% based on average Cd accumulation in the liver plus kidneys as the end point. Among Ca(NO3)(2), Zn(NO3)(2), and Fe(NO3)(2) supplements, 150-5000 mg kg(-1) Ca was the most effective in reducing rice Cd-RBA by 31-80% to 8.5-29%, while 30-200 mg kg(-1) Zn supplements was ineffective, with Cd-RBA being 33-57%. Low Fe at

We conducted a phase II, noncomparative, multicenter study to assess the efficacy and safety of allogeneic bone marrow‐derived mesenchymal stromal cells (BM‐MSCs) expanded in vitro for patients with aplastic anemia (AA) refractory to immunosuppressive therapy. Seventy‐four patients from seven centers received allogeneic BM‐MSCs at a dose of 1–2 × 106 cells/kg per week for 4 weeks. Responses were assessed at 0.5, 1, 2, 3, 6, 9, and 12 months after the first cells infusion. Patients with response at 1 month continued to receive four infusions. All patients were evaluable. The overall response rate was 28.4% (95% confidence interval, 19%–40%), with 6.8% complete response and 21.6% partial response. The median times to response of leukocytic, erythrocytic, and megakaryocytic linages were 19 (range, 11–29), 17 (range, 12–25), and 31 (range, 26–84) days, respectively. After median follow‐up of 17 months, overall survival was 87.8%. Seven patients developed transitory and mild headache and fever, but no other adverse events were observed. Antithymocyte globulin used in previous treatment and no activated infection throughout treatment were predictors for response. Allogeneic BM‐MSCs infusion is a feasible and effective treatment option for refractory AA. The trial was registered at www.clinicaltrials.gov as NCT00195624. Stem Cells Translational Medicine 2017;6:1569–1575

There is an electrical stimulation device for dental implant healing, which is designed for dental patients who have been received an implant in their jaws during the three months of healing period. The device consists of adjustable constant current (or constant voltage) circuit, power supply (including DC or external AC power supply and transformer), MCU(Microcontrollers), wire and electrode, electrode fixed and connecting device, control panel and shell. When the dental implants have been implanted, the instrument facilitates osseointegration between the implant and the alveolar bone and healing of the implant and gingival tissue. There is the most advantage that we can adjust the corresponding constant voltage (50-1000mV) or constant current (10-200mA)and the loading time(10-60min) depending on the patient's alveolar bone condition.

College students’ entrepreneurship should be combined with majors, based on professional knowledge as the core competitiveness, which is the basis of successful entrepreneurship. Dual embeddedness of social networks and industry networks is an inherent requirement to promote the growth of all entrepreneurial businesses. Features of embedded networks are different during different stages of college students’ entrepreneurship based on their professions. This determines college students’ entrepreneurial enterprises evolve from self-employed professional enterprises to professional enterprises and finally develop to product-innovative enterprises. This paper analyzes the effect of dual networks embeddedness on the growth of College Students' professional entrepreneurship from the perspective of embedded networks, making a few comments and suggestions in order to help students do professional entrepreneurship better and promote the growth of professional entrepreneurship.

Hand-to-mouth activity is an important pathway for children's exposure to contaminated soils, which is often co-contaminated by Pb and As in mining and smelting sites. To reduce soil Pb risk to humans by oral exposure, phosphate amendments have been used to reduce Pb relative bioavailability (RBA), but its efficiency has not been investigated using validated in vitro assays nor its influence on As-RBA. Here, 5 contaminated soils (A-E) were amended with 0.5% phosphoric acid (PA) to study its effect on Pb- and As- RBA using a newly-developed mouse kidney model and bioaccessibility using 4 in vitro assays including UBM, SBRC, IVG, and PBET. Based on the mouse kidney model, Pb-RBA in PA-amended soils decreased from 14.2-62.5% to 10.1-29.8%. In contrast, As-RBA decreased from 26.5% to 15.9% in soil B but increased from 27.5 to 41.2% in soil D, with changes being insignificant in 3 other soils (35.8-58.8 to 28.1-61.1%). When assessing Pb bioaccessibility in PA-amended soils, decreased bioaccessibility were found using PBET and SBRC. For As, its bioaccessibility increased in PA-amended soils, inconsistent with in vivo data. Our results shed light on the importance of method selection to assess risk in Pb- and As-contaminated soils amended with phosphate.

Biochar produced by thermal decomposition of biomass under oxygen-limited conditions has received increasing attention as a cost-effective sorbent to treat metal-contaminated waters. However, there is a lack of information on the roles of different sorption mechanisms for different metals and recent development of biochar modification to enhance metal sorption capacity, which is critical for biochar field application. This review summarizes the characteristics of biochar (e.g., surface area, porosity, pH, surface charge, functional groups, and mineral components) and main mechanisms governing sorption of As, Cr, Cd, Pb, and Hg by biochar. Biochar properties vary considerably with feedstock material and pyrolysis temperature, with high temperature producing biochars with higher surface area, porosity, pH, and mineral contents, but less functional groups. Different mechanisms dominate sorption of As (complexation and electrostatic interactions), Cr (electrostatic interactions, reduction, and complexation), Cd and Pb (complexation, cation exchange, and precipitation), and Hg (complexation and reduction). Besides sorption mechanisms, recent advance in modifying biochar by loading with minerals, reductants, organic functional groups, and nanoparticles, and activation with alkali solution to enhance metal sorption capacity is discussed. Future research needs for field application of biochar include competitive sorption mechanisms of co-existing metals, biochar reuse, and cost reduction of biochar production.

Mouse is an acceptable animal model to measure lead (Pb) relative bioavailability (RBA) in contaminated soils; however, there is a lack of comparisons among Pb-RBA measurements based on different endpoints and dosing approaches. In this study, 12 soils (47.8–8123 mg Pb kg−1) were assessed for Pb-RBA using Pb accumulation in mouse liver, kidneys, and/or femur following a 10-d steady state soil dose via diet, with 6 soils being measured using mouse bioassays with area under the mouse blood Pb concentration time curve (AUC) following a single gavaged dose as the endpoint. Based on individual endpoints of the steady state method, Pb-RBA in soils was 2.1–83.4%, being generally consistent among liver, kidneys, and femur with strong linear correlations between them (r2 = 0.74–0.89). To compensate variation in Pb distribution among different tissues, Pb-RBA was further calculated using a combined endpoint (e.g., sum of Pb accumulation in liver, kidneys, and femur). Compared to Pb-RBA based on individual tissue showing relative standard deviation (RSD) of 11.9–15.8%, Pb-RBA using the combined endpoint showed lower RSD (10.8%), thereby being more robust. For the 6 soils with Pb-RBA based on both mouse single gavaged and steady state dosing approach, no significant difference was observed; however, steady state approach was more repeatable among animals with lower RSD (11.4% vs. 34.5%). To ensure robustness of in vivo data, the steady state dosing approach with Pb accumulation in combined tissues is recommended. Refereed/Peer-reviewed

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.

Incidental ingestion of household dust is an important arsenic (As) exposure pathway for children. However, compared to soils, assessment of As relative bioavailability (RBA) in household dust is limited. In this study, As-RBA in 12 household dust samples (7–38 mg kg(–1)) was measured using an in vivo mouse model and compared to As bioaccessibility determined using 4 assays [Solubility Bioaccessibility Research Consortium method (SBRC), in vitro gastrointestinal method (IVG), Deutsches Institut für Normunge.V. method (DIN), and physiologically based extraction test (PBET)]. Arsenic RBA ranged from 21.8 ± 1.6 to 85.6 ± 7.2% with samples containing low Fe and high total organic carbon content having higher As-RBA. Strong in vivo–in vitro correlations (IVIVC) were found between As-RBA and As bioaccessibility for SBRC and DIN (r2 = 0.63–0.85), but weaker ones were obtained for IVG and PBET (r2 = 0.29–0.55). The developed IVIVC for SBRC and DIN were used to calculate As-RBA based on As bioaccessibility for an additional 12 household dust samples. Although As bioaccessibility differed significantly (up to 7.7-fold) based on in vitro methods, predicted As-RBA was less variable (up to 3.0-fold) when calculated using As bioaccessibility data and the corresponding IVIVC. Our data suggested that both SBRC and DIN had potential to assess As bioavailability in household dust samples; however, additional research is needed. Refereed/Peer-reviewed

We investigated the effects of arsenic species on As accumulation, plant growth and rhizospheric changes in As-hyperaccumulator Pteris vittata (PV). PV was grown for 60-d in a soil spiked with 200 mg kg(-1) arsenate (AsV-soil) or arsenite (AsIII-soil). Diffusive gradients in thin-films technique (DGT) were used to monitor As uptake by PV. Interestingly AsIII-soil produced the highest PV biomass at 8.6 g plant(-1), 27% and 46% greater than AsV-soil and the control. Biomass increase was associated with As-induced P uptake by PV. Although AsIII was oxidized to AsV during the experiment, As species impacted As accumulation by PV, with 17.5% more As in AsIII-soil than AsV-soil (36 vs. 31 mg plant(-1)). As concentration in PV roots was 30% higher in AsV-soil whereas As concentration in PV fronds was 7.9% greater in AsIII-soil, suggesting more rapid translocation of AsIII than AsV. These findings were important to understand the mechanisms of As uptake, accumulation and translocation by PV.

Children's blood lead levels and prevalence of lead poisoning in China are significantly higher than in developed countries, though a substantial decrease has been observed. Since 2011, strict lead control policies in lead-related industries have been implemented in China, but the success of these policies is unknown. In this study, we collected environmental samples, questionnaire data, and blood samples from 106 children from 1 to 14 years old, before and after implementation of lead-usage control policy in wire rope factories by local government in Zhuhang, Nantong in 2012. Results showed that, one year after the lead control, lead concentrations sharply decreased in both environmental and biological samples with a decrease of 0.43 μg/m3 (-84.3%) in ambient air samples, 0.22 mg/kg (-36.1%) in vegetable samples, 441.1 mg/kg (-43.7%) in dust samples, and 6.24 μg/dL (-51.5%) in childhood blood lead levels (BLL). This study demonstrates the success of lead control policies in promoting the prevention and control of childhood lead poisoning in Nantong, China.

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.

In this paper, the spalling causes of backup rolls in a roughing mill of a hot strip rolling mill were investigated. The roughing mill withstood extreme service conditions with long service cycles for backup and work rolls, a large variety of the same width rolling campaigns, severe and non-uniform wear contours of backup and work rolls. Analysis of cyclic stress applied on backup rolls indicated that contact stress played a dominant role in rolling contact fatigue which led to spalling on the backup roll surface. A 3D finite element model of roll system was established and contact stresses between rolls in whole service periods of backup and work rolls were calculated. The simulation results showed that roll wear had significant impact on contact stress distribution. In particular, the severe and non-uniform U-typed wear contours of work rolls led to produce huge contact stress peak in two sides of the rolls, where existed large cracks by eddy current inspection of post-service backup rolls. Backup rolls stood thousands of times stress cycle in a service period, they were liable to fatigue damage in these areas. A new backup roll contour was developed to improve contact stress distribution and no spalling accidents were happened any longer after applied to the roughing mill.

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.

This paper investigates the effects of surface spacing parameters on mixed lubrication based on a full numerical solution proposed by Hu and Zhu. Sinusoidal wavy surfaces with identical Ra and bearing area curve (BAC) but entirely different peak count ( Pc) are chosen to substitute the real textured engineering rollers surface. A set of mixed lubrication parameters such as average lubrication film thickness, ratio of contact area, ratio of contact load, and non-dimensional maximum pressure are introduced to analyze the effect of spacing parameters of surface on mixed lubrication performance. Numerical examples show that the spacing parameters have a significant effect on the contact parameters. That would be helpful for optimizing the textures, which are engineered into rollers surface for lubrication and wear performance improvement.

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.

Temperature and pesticide are two important factors that affect survival, reproduction and other physiological processes of insects. To determine interactions of elevated temperature and avermectins treatment on the western flower thrips, Frankliniella occidentalis, newly emerged adults were exposed to combinations of three temperatures (21, 26 and 33 °C) and two avermectins concentrations (0, 45 ppm), and survival rate, reproduction, longevity, antioxidant enzymes activities and heat shock proteins (hsps) induction were analyzed. The results showed that the survival, longevity and reproduction of F. occidentalis decreased with increased temperature and avermectins treatment. While elevated temperature and avermectins treatment significantly decreased activity of SOD, activities of POD and GST significantly increased after exposure to elevated temperature, avermectins or their combination. Elevated temperature had no effect on activity of CAT, but it was obviously improved by the combination of temperature and avermectins treatment. Expression analysis of hsps showed that four heat shock proteins (hsp90, hsc702, hsp60 and hop) were up-regulated by the induction of elevated temperature with small fold changes. After treatment with avermectins, expression levels of hsp90, hsc701, hsc702 and hop were significantly up-regulated with increased temperature and higher than those of their respective control at higher temperature. Surprisingly, expression level of hps60 was down-regulated with increased temperature, but the expression level at 21 or 26 °C remained higher than that of control. Overall, our studies suggest that elevated temperature enhance toxicity of avermectins and their combination induced acute oxidative damage to F. occidentalis. Therefore, consideration of temperature in evaluating avermectins toxicity is necessary to make accurate prediction of its effect on F. occidentalis and other insects.

We introduce an approach for making a ureteral tunnel with the aim of illustrating the importance of finding the tunnel dissection of the tissue spaces. The key to radical hysterectomy is identifying the tissue space that naturally exists between tissues rather than clamping a manual tunnel. For example, the urogenital sinus and Mullerian duct are very near each other; however, they never completely merge together. The method for finding the tunnel and avoiding the manual clamping of tunnels will maximally reduce intraoperative bleeding. Furthermore, the instructional significance of the surgery makes this technique worthy of promotion. Its main aspects include finding the gap, reducing or eliminating tunnel bleeding, and reducing collateral damage.

In International Union for the Protection of New Varieties of Plants member countries, assessment of wheat variety stability is a statutory requirement before new varieties are registered and plant breeders’ rights are granted. However, it is impossible to test the stability of varieties accurately and quickly, or to assess the stability of a large number of varieties in a short time based on the morphological traits defined by the national standard. The objective of this study was to establish method and procedure of wheat variety stability assessment using SSR markers as a replacement for morphological observations. In preliminary study, the methods to identify non-homozygous SSR loci and calculate the homozygous SSR loci ratio (SSR–HLR) of wheat varieties were established. On this basis, the genotypes at 347 molecular markers loci of 20 advanced lines demonstrated that SSR–HLRs were 84.7–94.8 % in the F4 lines, 96.1–99.4 % in the F5 lines, and ≥98 % in the F6 lines, respectively. Eighty of 347 markers with good polymorphism, stable PCR amplification, and high resolving power of genotyping were recommended to detect SSR–HLR for 633 wheat regional trial varieties. Comparing morphological observation, the varieties with SSR–HLR >95 % were deemed stable; the varieties with SSR–HLR

Many large shippers procure truckload (TL) service from carriers via a combinatorial auction. In order to determine the winners of the auction, they need to solve a combinatorial optimization problem known as winner determination problem (WDP). In practice, shippers must resolve the WDP under shipment volume uncertainty due to limited information of future demands. In this paper, we propose a sampling-based two-stage stochastic programming approach to solve WDP under shipment volume uncertainty. We propose a refined formulation of deterministic WDPs in which shortage in shipments and the associated penalty cost are explicitly modeled. We demonstrate that the refined model is more general and more feasible under uncertainty than the benchmarks. Theoretical results pertaining to problem feasibility are derived and their insights to TL service procurement are provided. We propose a sampling-based solution approach called Monte Carlo Approximation (MCA) and use numerical tests to show that MCA is numerically tractable for solving moderately sized instances of TL service procurement. Finally, we verify via Monte Carlo simulation that the solution to our proposed stochastic WDP yields lower procurement cost than the solution to the deterministic WDP.