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Most of slopes in nature have three-dimensional characteristics, such as displacement field, sliding surface, and mechanical mechanisms. Slope monitoring should take the three-dimensional characteristics into consideration to make monitoring networks arranged reasonably. In this paper, the Lijiazhai high slope on Shi-Ji highway is taken as engineering prototype. A similarity material of high density, low elastic modulus, and low intensity is produced. The deformation and failure characteristics of the high slope under moderate, heavy, and Torrential rain are simulated. The results show that the deformation of Lijiazhai high slope has obvious three-dimensional features. On bases of the model test, operational guidance and advice for long-term monitoring are provided.

In order to increase the performance of lift-type wind turbine, at the minimal torque value area, two interfere air flow is used to rebuilding the air flow. Based on multiply stream-tubes model, the effect of interfere air on promotion performance of blade element are studied. the results prove the interfere air method does greatly arise the torque, the attack angle of blade element at 0°~15 and 165°~180°azimuth angle, and promote the torque of single blade wind turbine with two or three blades. The paper provides a new way for vertical axis wind turbine designing and application.

Yttrium aluminum garnet (YAG) with a chemical composition of Y3Al5O12 is an important advanced structural and functional material.The preparation conditions were a pH of 9, a titration rate of 10ml/minute and a reaction time of 60 minutes. The analysis shows that the YAG precursor does not have an obvious characteristic crystalline diffraction peak, the characteristic diffraction peak of YAG was found after the calcination of the YAG precursor at 1100¡æ for 1 hour, the characteristic diffraction peak of YAG is strong, which indicates that the YAG crystalline phase is integrated and pure. The pore microstructure of porous YAG ceramics marked differed with an increase in the sintering temperature, the compressure strength of porous YAG ceramics is increased with an increase in the sintering temperature, the compressure strength shows the opposite rule with the prosity, which indicaties the mechanical properties of materials are effacted with the densification effect of materials.

To save land resources by the use of low-grade natural resources to realize a high cost performance product, the technology of prepared superfine quartz sand powder via the ball milling methods were investigated. The results are shown the mean particle size of quartz sand powder is gradually become small varied with prolonging the ball milling time. Before 60 minutes, the mean particle size is slashed, however, the range of varying mean particle size is less after 60 minutes under the ball milling rotate speed for 200r/min and the charge amount for 200g/L, so the ball milling time for 60 minutes is decided.The mean grain size of quartz powders are decreased vary with an increasing the ball milling rotate speed, and the rotate speed is lower, the distribution is wider, however, the rotate speed is higher, the distribution is narrower.The mean grain size of quartz powders are 11.25μm via a roller ball milling, the mean grain size of quartz powders are 7.37μm via a planetary ball milling, and the particle size distribution of quartz powders milled via a roller ball milling is wider than that of quartz powders milled via a planetary ball milling, which shows the of quartz powders milled via a roller ball milling is not more uniform than that of quartz powders milled via a planetary ball milling, the asymmetry powder is advantage for forming the high performance building materials body.

Based on the physical property analysis of sticky dust, the paper explained the effect of temperature, relative humidity, pressure, etc. on adhesion of dust. And focusing on these factors, take the silicon steel sticky dust for example, proposed two kinds of dust control technology: pipeline heat tracing technology and gas conditioning of SO3, both help improve system efficiency by selecting the appropriate dust collector.

In order to research the resistance characteristic of silicon-based composite tiles under high temperature thermal load on aircraft during its reentry into the earth's atmosphere, the ordinary resistance measurements were comparatively discussed according to the operational environment of composite, two parallel electrodes probe test method was proposed, and the resistance test platform under high temperature thermal load was developed, by which the resistance characteristic of silicon-based composite tiles was continuous monitored under different thermal load. The result shows that: If the temperature is not higher than 600°C, the resistance will increase with the decrease of temperature until it reached the resistance value at room temperature; If the temperature is higher than 700°C, the resistance characteristic will be changed everlastingly; If the temperature is higher than 800°C, the resistance will be less than 1kΩ and will not change any more.

As one of China's traditional habits, setting off firecrackers during the holiday season has been going on for thousands of years, especially in north China. This paper selects the atmospheric environmental quality real-time data published by China environmental department, including the AQI, PM10 and PM2.5, sulphur dioxide and nitrogen oxides. It shows that all pollutants have a rising trend during the Spring Festival period, especially from 20:00 at lunar 30th to 4:00 at lunar New Year's Day. From the analysis on the cause, setting off firecrackers during the Spring Festival is the direct cause of the decline in air quality.

Vegetation index time series data modeling is widely used in many research areas, such as analysis of environmental change, estimation of crop yield, and the precision of the traditional vegetation index time series data fitting model is lower. This paper conducts the modeling with introducing the autoregressive moving average time series model, and using NOAA/AVHRR normalized differential vegetation index time series data, to estimate the errors of original data which are between under the situation that the parameters to be estimated are lesser, and on the basis gives the fitted equation to the six kinds of main land covers’ vegetation index time series data of Northeast China region.

Due to the presence of complicated and considerable amounts of toxic compounds such as phenolic compounds, thiocyanate and ammonium, coal gasification wastewater (CGW) would cause a serious environmental problem. Conventional treatment of CGW includes a series of biological treatment (mostly anoxic-aerobic process and activated sludge process) after a physico-chemical pretreatment to reduce the concentrations of phenols and ammonium. Although quite effective, these processes are still not enough to meet the strict requirements of the National Discharge Standard of China. To find more efficient way to treat CGW, a serious of hybrid processes were reviewed in this study. Through this review we found that A2O combined with MBR (anaerobic-anoxic-aerobic membrane reactor) can effectively remove COD, total organic carbon, NH4+ -N, total phenols and total nitrogen (TN).

Coking wastewater contains high concentration of refractory and toxic compounds. The effluent quality usually cannot meet the discharge limits after single conventional biological treatment processes. In order to find more effective coking wastewater treatment process, a serious hybrid treatment process were reviewed in this paper, which include: anoxic-anaerobic-oxic(A2/O) combined with membrane bioreactor (MBR); Fe/C micro electrolysis combined with Fenton process. Fenton oxidation combined with biologically process. Wastewater quality and operating parameters were compared. Through this review, we found that hybrid process is more efficiency to treat coking wastewater.

In order to seek a better way of control in sewage treatment, a control system which consisted of water unit, sand unit, the oxidation ditch unit, precipitation unit and sludge dewatering unit was designed. The paper investigates various controllable parameters in sewage treatment system and the way of present common automation control. We designed manual control variable aeration program and two automatic control subroutine which included thickness grille and pumping station by using WIN 32 software. The program is designed in Siemens STEP 7 V5.5 software development platform and chose the 10 input contacts which are I0.0~I0.7, I1.0~I1.1 and 10 output contact which are Q1.0~Q1.1, Q0.0~Q0.7.This design achieves automatic control and improves the purifying efficiency on the premise of ensuring water quality.

In order to strengthen the communication between students and teachers and improve the teaching effect.In this paper, a kind of excellent course website based on Wordpress was designed.Set up different levels user system by station group, by which the communications between each network module realized. Teacher can build their own page as substation administer.In this paper the key steps of the construction were descripting in detail. Experiments show: it is a reliable and effective website construction scheme with simple extention and maintenance.

The process parameters and quality of resistance spot welding for DP980 dual phase steel were studied through the orthogonal experiment method, and the influence of welding current, welding time and electrode force on the strength of welding joint has been discussed. The results show that the welding current has the greatest influence on the quality of welding joint for DP980 dual phase steel, and it needs relatively lower welding current for the DP980 dual phase steel as it has high resistivity, and appropriate increasing of electrode force is a feasible way to avoid the defect of shrinkage and it improves the joint strength.

In this paper three-rubber compression packers are regard as study objects, hyper-elastic constitution equation Yeoh has been used, the ANSYS mechanical model of packer rubber has been established by ANSYS software, the influence of axial setting force and frictional coefficient on the contact stress of packer rubber has been analyzed. The research results indicate that with the increasing of setting force, the axial compression amount and Von Mises stress increase; with the increasing of frictional coefficient between rubber and casing, the Von Mises stress of the intermediate rubber decreases slowly.

Four cinchona alkaloid-silyl ether derivatives have been used to catalyze the asymmetric “interrupted” Feist-Bénary reaction of ethyl bromopyruvate/substituted bromo-ketoesters and 1,3-Cyclohexadione. The corresponding hydroxydihydrofurans have been obtained in excellent yields (85-96%) with high enantiomeric excess (ee) values of up to 90%.

In order to improve the level of automation and realize remote control of the transformer temperature control system, a fast remote automatic control system that based on the chip TMS320C6713 was designed by us. Using four temperature sensors (Pt100) tow amplifier and analogy to digital (A/D) convertor detect deal with the signal of the temperature of winding and environmental. According with the temperature of transformer to control the cooling device switch on or off, the service life of the radiator was extended. In the design the digital signal processor (DSP) chip is communication with the central control room through the RS-485 bus, which makes the remote transformer temperature monitor into reality. In addition, this system is more versatility and reliability than the traditional device.

It is urgent to study a new control system for improving the efficiency of electrostatic precipitator. The System-on-a-Programmable-Chip (SOPC) development board, which belongs to the series of Cyclone of Altera Company, is used as the development platform. Analog Digital (AD) conversion module, voltage control module and overall control module of the electrostatic precipitator are designed and the simulation waveform of the system is analyzed, based on the programmable logic device EP1C12Q240C6 and Very-High-Speed Integrated Circuit Hardware Description Language (VHDL) programming language. The results show that: by using Field Programmable Gate Array (FPGA) as the control, transformation of AD is accurate and fast and high voltage power supply is stable, which leads to a certain value for generalization.

Piezoelectric actuator is compared. The tension and compression symmetrical dual piezoelectric-stack actuator, studied in this paper, is presented finally. The structural principle of this actuator is introduced. The finite element model of this actuator is built up also. Dynamic performance of this actuator is simulated by the MATLAB Simulink, and the results of simulation are in agreement with that of the experiment.

By using numerical simulation method,the three-dimensional flow field of air supply cylinder using for displacement ventilation in industrial plant is analyzed. The internal structure, effective wind sent area and the shape of wind outlet small hole which affected the air outlet wind speed of air supply cylinder are researched. While compared with the simulated and measured result of the outlet velocity of the wind outlet small hole, the best feature parameters of wind speed in air supply cylinder has been gained. The result shows that: by changing the internal structure and decreasing the effective air supply area of the air supply cylinder, the wind speed from the air-outlet on the small hole can be more reasonably distributed; although by increasing the effective air supply area and changing the shape of outlet hole on air supply cylinder will make the air outlet be more effectively distributed, its value is unreasonable.

The ANSYS-ICEPAK is used to establish and analyze the thermal condition of the cooling modular of the looped pulsating heat pipe in the street light, the reliability is proved by experimental results of thermal analysis. The experimental results show that: the temperature distributions on the surface of the lamp shell and loop heat pipe are uniform, and the average temperatures of them are about 40°Cand 43°C; while the maximum temperature of the chip base reaches 67.5°C. Through comparison, the simulation results are close to the actual measured results.

In this paper, a new type of AC-AC contact-less power transmission system based on the specific engineering environment is produced. A new loosely-coupled transformer structure and its working type are developed. Besides, a new set of high efficient based on the qusai-resonant technology is realized. Theoretical calculation and simulation software are used to prove its feasibility; a series of experiments are completed. Finally, the contact-less power transmission system functions well.

The objective of this research is to describe a three-dimensional force measuring system operating in wind tunnel test to investigate the static and dynamic effects of buildings under wind loads. A three-decker structure serves as the elastic element of the three-dimensional force sensor. The solution for overload in the courses of transport, installation and employment is proposed. The set-in hardware circuit is devised to improve the signal-to-noise ratio. A portable box of multiplex data acquisition was designed to achieve synchronous measurement. Multiple sensors were utilized in the measurement of the reacted forces for a rigid model with multiple supporting components in wind tunnel test. The experimental results could provide reference value and significance in the innovation and engineering of industrial measurement.

In allusion to the disadvantages of sucker rod displacement measuring technologies at present, we introduce an inertial measuring technology in which the design of acceleration measuring system, the design of IIR digital filter and double integral algorithm play significant roles. Through combination of hardware and software, the embedded measuring system was developed to measure the acceleration, process data and realize the serial communication. In our practical work, some chips were used in this system, eg 1221L-002, ADS1259, MSP430F1611, MAX202, etc. The test results showed that the accuracy of the measuring system reached to 5%, which met the request for oilfield.

Circumferential magnetization of the thick wall steel pipe is carried out for the inspection of longitudinal defects in magnetic flux leakage testing. For high precision magnetic flux leakage testing, magnetic field distribution along the axial direction must be uniform, thus a new type of pole shoe structure is proposed in this paper to enlarge the uniformly magnetized area. Thick wall steel pipes are hard to be magnetized to near saturation, especially when the new pole shoe is used, which makes difficult for the magnetic sensors to pick up the magnetic leakage field. Therefore, the relationship between the magnetic flux density of the detection zone and the dimensions of the magnetizer has been studied by finite element simulation. These results are helpful in the design of circumferential magnetizer.

Combining with the advantages of the piezoelectric material, positive and negative torque actuator using dual piezoelectric-stack is developed for vibration active control of annular flexible structure in this paper. The working principle of the actuator is described, and the output performance of the actuator is tested in this paper. Also the actuator is applied successfully to the vibration active control of annular flexible structure.

A robust, accurate and sensitive analytical procedure was developed for the simultaneous determination of trace Antimony and Bismuth in Jilin ginseng by hydride generation atomic fluorescence spectrometry. The parameters were studied systematically, such as acid concentration of the reaction medium, flow rate of the carrier gas and shield gas, the atomizer of height, etc. Ascorbic acid and thiourea were used as reducer or masking agents to enhance the generation efficiency of the volatile species of Sb and Bi. In the presence of thiourea and ascorbic acid, the influences of some coexisting elements on the determination of antimony and bismuth were investigated.

An improved allocation method was proposed to determinate SO2 emission control quantum for certain control area, which was achieved by least square optimization with environmental constraints. In order to avoid local air pollution happening, the concept of potential pollution distribution factor was introduced to determine SO2 actual environmental capacity. In the method, more SO2 emission right and emission trading chances among sub control areas were offered. The case analysis indicated the method was more suitable for emission trading compared with equal-right function method.

In this paper,the model of the trident chamfer, which is the twin tripod sliding universal joint used in small rolling mill, is created by the software Solidworks, and the statics has been analyzed by using the software ANSYS Workbench. The stress contours diagrams and the deformation contours diagrams of the trident chamfer are obtained,so as to arrive its stress distribution and deformation. So the maximum stress concentration parts of the trident chamfer are known by being analyzed. Similarly, The maximum deformation concentration parts are obtained. All above of this provides the theoretical basis for the further study of twin tripod sliding universal joint, especially in the improvement of the structure as well as the heat treatment of the material.

In the view of the disadvantages brought by DMC(digital magnetic compass) and gyro when they are used separately, a combined directional instrument composed by a 3-axes digital magnetic compass and a 3-axes MEMS gyro for vehicles is introduced, which is less influenced to the magnetic field interference and random drift. In the abnormal magnetic field, the MEMS gyro is used for correcting the heading angle of DMC. The experiment data shows that this instrument can output a stable and high-precision heading angle. It can be used to provide heading angle for vehicles.

In this paper, a kind of pedestrian navigation system (PNS) that based on Earth’s magnetic field is introduced, and the error of the build-in electronic compass is analyzed, and an efficient calibration algorithm is presented. The PNS is determined pedestrian’s movement locus by calculating the heading angle and analyzing the movement characteristic, and then using the dead reckoning algorithm to combine the information together. The precision of PNS is affected by the error of the electric compass, because the heading angle is calculated from the magnetic field data measured by the compass. In order to reduce the measure error, a direct method which is used to calibrate the compass, based on ellipsoid fitting, is developed.

A model on non-sinusoidal oscillation of continuous casting mould was established to study the pressure in flux channel. The effects of oscillation parameters on the pressure in flux channel were researched. The non-sinusoidal oscillation parameters were optimized. When the casting speed is 1.8 m·min-1, the optimized oscillation parameters are: non-sinusoidal factor (α) is 0.198, oscillation amplitude (s) is ±4mm and oscillation frequency (f) is 165min-1. When the casting speed is 2.0 m·min-1, the optimized oscillation parameters are: α is 0.186, s is ±4.5mm and f is 155min-1. These optimized oscillation parameters are proved applicable in practice.

Grouting is often adopted in a tunnel to resist high external water pressure; the tunnel is defined as External Water Pressure-Resistant Tunnel (EWPR Tunnel). When the grouting reinforcement does not seal the high pressure groundwater completely and the leakage groundwater is drained by drainage system, the tunnel can be called a Drained External Water Pressure -Resistant Tunnel with limited Drainage (DEWPR Tunnel), the grouting reinforcement and waterproof/drainage system of which are great important and should be considered specially. Take the traffic tunnels of Jinping Second Cascade Hydropower Station as an example, a numerical method is adopted to simulate the influence of grouting reinforcement thickness on the distribution of external water pressure. The results indicate that the discharge rate per unit length is 7.82m2/d with single tunnel drainage and 5.28m2/d with double-tunnel drainage, and the external water pressure can be reduced less than 0.6MPa when the thickness of grouting reinforcement is 12m based on the control factor of volume of water discharge.

One dimension consolidation equation can be transformed into a fractional differential equation by Laplace transform. The transformed equation can leads to a simple relation between pore water pressure and its time revolution. When local rate of change of the pore water pressure is determined, the local pore water pressure can be obtained without having to solve the consolidation equation within the entire domain. The simplicity of the solution procedure is highlighted considering by a example..

In recent years, wire sawing is considered to be a potentially better technology of slicing brittle crystals especially semiconductor, owing to the unmatched advantages of slicing large ingot into thin wafers with high efficiency, fine quality and less kerf loss. This paper analyses the dynamic effect on wire from a variety of excitation and mechanical structure in the process of cutting on the basis of the effects of vibration on slicing wafer quality. A suitable model is built according to Hamilton principle, closed form expressions is present for the steady state response using finite element method. The relation between inherent characteristics of wiresaw and different system parameters is obtained.

In this work, triethyl phosphate (TEP) was used to bioactivating titanium. Titanium plates grafted with TEP were immersed in a two times concentrated simulated body fluid (2SBF) to investigate deposition of hydoxyapatite (HA) on the surface. A phosphate buffer solution (PBS) with bovine serum albumin (BSA) was used to evaluate adsorption of protein on the grafted titanium surface. The morphology, component and structure of samples were examined by scanning electronic microscopy, attenuated total reflection Fourier transform infrared spectroscopy and X-ray diffraction respectively. The concentration change of BSA in adsorption test was examined with the ultraviolet-visible absorption spectra (UV). The analyses showed that TEP grafted onto the titanium surface. In 2SBF, calcium and phosphate ions deposited spontaneously onto the grafted titanium surface and formed a HA coating with a network-like microporous structure after being immersed for 3 days. The coating consisted of HA particles with 180-265nm in thickness and 72-85nm in width. The diameter of the micropores was about 200nm. The HA coating appeared better uniformity than that on the modified titanium using phosphoric acid. BSA rapidly adsorbed onto the grafted titanium surface at first half an hour and then the adsorption quantity almost kept constant. These results indicate that TEP grafting is an effective approach to modify bioactivity of titanium.