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The distribution of the temperature gradient and temperature change of the pre-stressed concrete box girder are extremely complicated because of the multiplex environment. Temperature load has attached great importance in the field of engineering, and it has a great influence on the bridge’s structure, especially the box structure. The engineering background of this paper is a typical three-dimensional pre-stressed concrete continuous box girder bridge with variable cross section, comprising five spans in one continuous unit. Experiment on it and research the change rules of the temperature distribution, as well as the influence of the structure’s internal force resulted by temperature. Finite element software-Midas/FEA is used to model and calculate the bridge in order to analyze the temperature influence on structure’s stress in contrast to the measured data from the experiments

A technique for a reconditioning equalizer filter for non-constant envelope signals is described. The input to a transmitter chain is modified by a reconditioning equalizer filter, prior to being applied to the transmitter. The reconditioning equalizer filter modifies and smoothens the amplitude of the signal. The modified and smoothened signal has its peaks reduced which results in lower Crest Factor. The input to the reconditioning equalizer filter could be a baseband, intermediate frequency (IF) or radio frequency (RF) signal. When the signal is an IF or RF signal, it needs to be down-converted to baseband before being applied to the reconditioning equalizer filter. The reconditioning equalizer filter could be performed in a digital or analog domain.

A basic experiment study with a simplified wing model was carried out to introduce a opposite wake vortex by different sizes of spoilers. A PIV measurement was employed to obtain a two dimension wing wake vortex velocity field data of different spoilers in a water towing tank and confirm the existence of Reyleigh-Ludwieg instability in aircraft wake vortex. The image preprocessing is useful in PIV post-processing by comparing the three kinds of image preprocessing results with normal PIV image processing results.

From the perspective of stress and heat distribution, the influence of material and heat on working reliability of the turret seal is analysed. Based on the actual working condition of a servo turret, the FEA (finite element analysis) of structural mechanics and thermal structural coupling is carried out on the key reciprocating seal between piston and oil cylinder. The analysis re that material hardness and temperature have great influence on the seal contact pressure and the leakage. To be specific, the lower seal material hardness leads to the lower maximum contact stress and longer seal’s service life without increasing the net leakage under 3.5 Mpa oil pressure. The result demonstrates that the material with hardness 90 is better than that with hardness 95 under the hydraulic pressure 3.5Mpa. Besides, temperature distribution of seal under the working condition is gained through the thermal structural coupling analysis. It is concluded that increasing temperature lead to decreased leakage and enhanced contact stress. Consequently, the influence of the temperature should be taken into consideration on the research of seal numerical model.

NC Turrets include Servo Turrets and Power Turrets. The structural differences of them are addressed. In this paper, data storage structures of turret parts, turret automatically assembled, finite element analysis, optimization design and 3D model browse in the WEB are studied. Based on the construction of B/S, a NC Turret rapid development platform which is composed by Network user tier, WEB business tier and Data tier is constructed. The platform integrates a CAE analysis module based on ANSYS, a parametric design module based on SolidWorks and a reliability analysis module based on MATLAB. The Rapid Development Platform can perform the new product design and reliability analysis, and an optimal develpoment design of NC Turrets can be realized rapidly and efficiently.

A Plackett–Burman design was employed to investigate the effect of various parameters on the denitrification effect of high salinity wastewater treated by biofortification SBR.The purposes of this study were to investigate the significance of pH, DO, C/N, the initial ammonia concentration, salinity, the amount of bacteria and sludge concentration (MLSS).Factors which have significant influence on the denitrification effect of biofortification SBR treatment are quickly screened and used to establish a mathematical model.The results of quick screening provide critical factors for the optimization of operating parameters.

The traceability system is an important means of improving the quality and safety of agricultural products. Through a study on domestic and international traceability system, this paper presented a hybrid architecture based on the combination of Client/Server and 3-tire structure. The research work employed geographic information system, database technology, web technology, barcode, anti-counterfeiting code and .Net framework technology, thus a traceability system has been realized in which all the quality information is traceable through all the process, and all the agricultural products circulation routes and areas affected by inputs could be clearly displayed in geographic space.

This research adopts the important iron electrolysis, removal of the wastewater of high COD, SS, phosphorus pretreatment experiment. Discusses the different iron dosing quantity, iron carbon ratio, and pH value, reaction time on the COD and turbidity, the influence of the phosphorus removal effect. Studies show that iron important electrochemical test in brewery wastewater treatment static optimal processing conditions for: water pH value is 4, 5% dosage of iron filings, 60 min temperature response, COD removal rate was 52.31%. When the iron carbon ratio of 2:1, removing effect is good, can reach 54.53%.

The analytic hierarchy process is a comprehensive evaluation method, which is a combination of qualitative analysis method and quantitative analysis method, it can simplify the complex problems; this article mainly introduces the features and specific algorithm,carry out a comprehensive evaluation concerning about analysis of problems of on line monitoring about liaohe rive basin water pollution source through layers analyzing method, and compare the rankings to provide thinking for the improvement and optimization of the on line monitoring about liaohe rive basin water pollution source.

Seven-bar seedling planting mechanism is one kind of developed transplanting mechanism of vegetable seedling transplanting machines. Dynamic equations of the link rods were established and analysis program was compiled so as to analyze the dynamic characteristics of the mechanism; Meanwhile, simulation model of the mechanism was established and corresponding virtual dynamic test was conducted based on Adams. The consistency between calculation results based on kinematic theory model and simulation results achieved from Adams was proved through comparison, which verified the dynamics model was correct and reliable. It can be concluded that the dynamic model was the basis of dynamic parameter optimization model of seven-bar seedling planting mechanism, which facilitates the parameter optimization process of the kind of seedling planting mechanism with various specifications, and it also avoided the tedious process of repeated modeling based on Adams dynamics optimization. With the analysis results of the seven-bar seedlings planting mechanism based on the established kinematic model, it was found out that the force fluctuation at the chassis caused by the reciprocating motion of the mechanism was large, which could cause machine vibration and increase the labor intensity of operators.

Automatic monitoring indicators system of pollution is the key and foundation to construct network of pollutions in total amount monitoring.Scientific and reasonable indicators system can reflect pollutant situation and influence on water environment.Automatic monitoring indicators in pollution of sources are confined to COD and ammonia nitrogen as well as short of monitoring indicators to character features of pollutional sources.It is necessary to conduct optimization and selection of automatic monitoring indicators.Based on beer manufacturing in demonstration area as the research object,analyze sources of pollution in Qinghe basin producing and sewage situation;adopt screening methods to complete optimization and selection of automatic monitoring indicators.Build the system of automatic monitoring indicators in beer manufacturing successfully to provide theoretical support for constructing network of water pollutant total amount monitoring.

The implementation of a project contains a lot of uncertainty, by their nature, random uncertainty, uncertainty and human factors (such as peoples limitations of understanding things and design methods, the use of analog approximate calculation results) due to the uncertainty of the future to better improve the structural reliability, this paper, the probability model reviewed structural reliability.

Direct reduced iron (DRI) shaft furnace flow field has important influence to the DRI production process, and the ventilation is a key factor for the velocity and pressure distribution of the gas flow in the furnace. At present works, the direct reducing gas velocity distribution and pressure distribution of DRI shaft furnace were studied with different ventilation. By the analysis of numerical simulation, the result was found that the direct reducing gas velocity increase with height in the shaft furnace reduction section. The velocity of the direct reducing gas augment with the increase of ventilation. The direct reducing gas pressure add with increasing height in the shaft furnace reduction section. With ventilation increasing, the pressure of the shaft furnace ventral part increase, and the pressure gradient increase in the direction of height in the DRI shaft furnace.

The system uses the latest computer and RFSN induction smart card technology, with the principles of scientific, advanced, reliable and economy, and it is developed on the basis of many factors. Installing a set of import and export management facilities on the Entrances and exits of the parking lot, parking spaces will form a relatively closed space. When the vehicle is entering or exiting, the system captures images and recognizes vehicle license automatically etc,to make video surveillance of vehicles, real-time recording Vehicle access images, accounting, and so forth. It will be an effective work to control, monitor, and manage parking lot, reducing the operating costs of the parking lot, and to prevent steal vehicle behavior, which protects the interests of management and owners. Keywords: Program; Automation; RFSN

The numbers of index of Chinese standards for drinking water quality increased from 17 by the Health Regulation for Drinking water promulgated 1959 to106 by the current Standards for Drinking Water Quality (GB5749-2006). The Standard has been developed at the same pace with the world. However, there were some hysteretic problems in the process of standards implementation due to the detection technique. The article was aimed at making suggestions on improving detection capability and testing equipment, making programs on the technical personnel and the regional differences. The present research results will lay the foundation for the implementation of Chinese standards for drinking water quality.

Telephone is one of the most convenient tools for getting informations to users. For the purpose of querying the quality traceable information for agricultural products, this paper presented a own-designed telephone voice query system. The software design of this system is based on 3-layer structured software, and adopted thread technology, database technology and Text-to-Speech(TTS) technology. This system is actually being used in China State Farm Economic Development Center.

In this paper, firstly, the function of test-bed of motor-wheel-drive Electric Vehicle has been clarified, the frame structures of test-bed has been designed and built. Secondly, control algorithm of motor-wheel-drive Electric Vehicle has been established, including vector control algorithm model, digital PID algorithm model and electronic differential control algorithm model, the control system of test-bed has been designed. Lastly, based on the test bed, the control algorithm of motor-wheel-drive Electric Vehicle has been verified by bench test. The bench test results show that, the control algorithm of motor-wheel-drive Electric Vehicle can achieve straight-ahead control and steering control, which laid the foundation for the future of the real vehicle tests.

The Electric Differential Control for Motor-Wheel-Drive Electric Vehicle is discussed. And then the self-regulation method to realize the electric differential by controlling the torque of the motor and freeing the speed of the wheels has been proposed. Firstly, tire-road dynamics modeling has been established, Control system of Motor-Wheel-Drive Electric Vehicle has been designed. Secondly, simulation platform of Motor-Wheel-Drive Electric Vehicle has been established. Lastly, simulation for electric differential control of Motor-Wheel-Drive Electric Vehicle has been validated. The simulation results show that the self-regulation method by controlling the torque of the motor and freeing the speed of the wheels is effective. Each wheel speed and the corresponding wheel speed automatically keep coordination; it can realize the self-regulation differential, no wheel slipping or sliding phenomenon.

Through running anaerobic ammonia oxidation reactors for a few days, we found that inorganic carbon source has great influence on anaerobic ammonia oxidation reactions. The inorganic carbon source increasing, the effect of anaerobic ammonia oxidation bacteria reaction is much better and the processing rate is high. And if there are no inorganic carbon source, anaerobic ammonia oxidation reactions are running anomaly. The processing rate of nitrate nitrogen is about 80%, and the processing rate of ammonia nitrogen is only 30% or so. The anaerobic ammonia oxidation bacteria metabolic is getting worse and worse.

The invasion of indigenous flora from the open system into the biological enhanced activated carbon(BEAC) system can inhibit the development of dominant bacteria and also decrease the biodegradability and biological activity of dominant bacteria. Therefore, this study aimed to investigate the effect of backwashing on the indigenous flora and dominant bacteria in the BEAC system and to study the optimal operation process of backwashing. In order to control the inhibition of the indigenous flora, the optimal backwashing conditions were set as 7-10d of operation period and 8-10 L/(m2•s) of air backwashing intensity. In addition, the PCR-DGGE results showed the indigenous flora could be removed under the optimal backwashing process, and the dominant bacteria could also be updated to maintain the biological stability well in this system.

China has the largest population in the world, and the available water resources per capita are very limited. The rapid economic growth and urbanization has caused increased water demand in China’s urban areas. Urban water quota management has become a core strategy for establishing a water-saving society. In 2001-2008, the trend of total water consumption has changed obvious in China. And the water consumption of public service has the same trend. Whit the development of the third industry and the increase of use efficiency, in the future the trend of public service water consumption will maintain stable situation. It still need further improve the water management to control the water increasing. The comprehensive water quota as the standard can estimate the water-saving level of the industries. And it can also determine whether the industry meet the water-saving requirements. Compared with the part quota, it simplifies the process of collecting the water data and improving the quota management operation, which avoid the false data. Researching the comprehensive water quota is a critical part of water quota management.

The experiment uses the Shenyang northern sewage treatment plant two sink the pond sludge was the indigenous Thiobacillus enrichment culture, through the matrix of different proportion, to find the most suitable matrix proportion, so as to shorten the bioleaching process start time, improve the bioleaching process for heavy metal removal efficiency. By usihng the method developed by mixing S bacteria predominantly mixed bacteria liquid, will raise the mixed strain cycle was shortened to 11 days, the best ratio of S, Fe2+ matrix is determined as 3 : 1, the matrix culture mixed Thiobacillus is faster, and can greatly improve the bioleaching boot efficiency. Fe2+ dosing is able to activate the bacterial Fe2+ enzyme synthesis, be helpful for accelerating thiobacilli on s oxidation using elemental sulfur, while also promoting microorganism to use Fe2+. Using the technology of biological leaching experiment on heavy metal removal rate is higher, compared with a single strain has more engineering application and popularization value.

The passage makes an analysis about water utilization structure by consulting literature and questionnaire survey. Household water consumption rose steadily and its proportion in domestic water rose from 39.8% in 1999 to 66.8% in 2008, and the flushing and bathing accounted for the largest amount of household water, its proportions is 27.1% and 26.4%. The bathing water of the southern city was wasted; it produces water-using potential. So the prevalence rate of the advanced instruments is important for using water efficiently.

Simultaneous powdered activated carbon(PAC) adsorption and dominant bacteria biodegradation process was evaluated for the aniline pollution accident existing in source water. The jar test results showed the aniline adsorption capacity and adsorption rate of the PAC were represented by the Freundich adsorption isotherm model. The aniline adsorption ability of the PAC was high when the temperature was low; the biological activity of dominant bacteria was high when the temperature was at 25°C and pH value was at 6. The poly-aluminum-chloride in combination with PAC and potassium permanganate in combination with PAC were compared with the simultaneous adsorption and biodegradation.

Two different kinds of water were treated with aeration-contact oxidation filtration process. One was groundwater containing iron and manganese (GIM), the other was GIM polluted by ammonia (GAIM). The results showed that ammonia has almost no influence on iron removal, but has great influence on manganese. Under the condition of 1m/h filter velocity and 10 mg/L average ammonia nitrogen concentration of inlet，the outlet manganese concentration for GAIM was less than 0.1 mg/L after 315 days. When temperature dropped to 18°C below, the manganese concentration of effluent exceeded 0.1 mg/L. When average ammonia nitrogen concentration of inlet for GAIM dropped to 3.27 mg/L, the manganese concentration of outlet for GAIM was less than 0.1 mg/L in winter. And for GIM, the manganese concentration of outlet was less than 0.1 mg/L only after 52 days. Although the filter velocity increased gradually from 1 to 7 m/h, the manganese concentration of effluent was always less than 0.1 mg/L. Therefore, ammonia pollution in the groundwater greatly increases the difficulty of water treatment.

The current situations of water environmental problem, water quality, water pollution prevention and control of the Liao River are analyzed and evaluated in this paper. The results show that a serious current situation of the Liao River water quality. The main pollution sources are: grave mountain forest vegetation destruction; serious soil and water loss; densely populated city; great pressure of sewage treatment; low coverage rate of the urban sewage pipe network; serious phenomenon for sewage straightly discharge and level of recycled water reuse. This paper aims at putting forward more attention on the work of basin pollution prevention and treatment; fundamentally relieve water source-oriented supply pressure.

A discrete sliding mode control based on reaching law is investigated to suppress vibration of high-speed flexible manipulator. The finite element method and experimental modal test is applied to obtain the dynamic model of the system. Due to the influence from uncertain external disturbances and measurement noise, and uncertain parameters, sliding mode control has invariance of the sliding mode. The discrete sliding mode control approach with reaching law is applied to design the vibration controller which enables the system to be zero state as the system states are away from the equilibrium one due to external disturbances. The discrete Kalman filtering technique is employed to construct state estimator because the state variables cannot be directly measured. The first three natural frequencies and damping ratio are obtained by using experimental modal testing. The experimental control system is constructed and experimental validation is carried out using dSPACE real-time simulation system and MATLAB/Simulink. The experimental results showed that the proposed controller can effectively suppress the vibration response of the flexible manipulator.

Cavitation typically occurs when the fluid pressure is lower than the vapor pressure at a local thermodynamic state. The aim of this paper is a numerical investigation of the cryogenic cavitation flow characteristics, considering variable thermodynamic properties of liquid nitrogen and numerical simulation liquid nitrogen around hydrofoil cryogenic cavitation flow characteristics. Based on homogeneous flow model and Zwart cavitation model, calculates hydrofoil isothermal and cryogenic cavitation in liquid nitrogen steadily, updates the evaporation and condensation coefficients of Zwart cavitation model, gives the hydrofoil surface pressure profile, temperature depression and distribution of cavitation intensity, contrasts the isothermal and cryogenic cavitation flow characteristics. Numerical results show that thermodynamics effect in cryogenic liquid cavitation significantly. Meanwhile, the hydrofoil surface pressure and temperature numerical results with experimental data and more Hord compared to verify the validity of the numerical simulation.

An optimization design method of a hyperbolic flexible hinge is presented in this paper. According to the structure feature and force exerted on the flexible hinge, the closed-form equations are formulated for compliances to characterize both the active rotation and all other in- and out-of-plane parasitic motions by using the Castigliano’s second theorem. Meanwhile, the accuracy equations of the hyperbolic flexure hinge are obtained using the Castigliano’s second theorem. The in-plane rotation angle of flexure hinge is optimization objective, and the constraints of optimization model are out-of-plane displacements and one described the accuracy of hinge, such that the optimization model can be established to meet performance requirements of flexure hinge. Based on the optimization model, the optimization designs of hyperbolic flexure hinge are performed to acquire its optimized structural parameters. And the optimization results have showed the optimization process can meet the design requirement.

It is indicated that the fluid flow does not abide by the Darcy law in certain low permeability reservoirs. The results of pressure date analysis in these low permeability reservoirs would be inaccurate when generalized using Darcy flow models. To improve analysis results, based on the concept of variable permeability effect, the dual non-Darcy coupling flow model is established in this paper. The iterative algorithm is adopted to solve the differential set of equations. This work also describes the pressure behaviors by pressure response curves.

To measure the similarity between two images, the local information around all the points were usually used for traditional image retrieval methods based on interest points. The accuracy would be influenced by the dissimilar interest points in the background region or in the uninterested regions. A new image retrieval method based on interest points was proposed in this paper. The most similar interest points were chosen firstly based on feature matching techniques, then the similarity was measured based on the local gray information around the preserved similar interest points. Experiments show that the proposed method is more accurate than traditional image retrieval method based on interest points.

Firstly, this paper proposed that charging network for Electric Vehicle (EV) should be consisted of the special motorcade charging system and general charging system mainly, and the emergency charging system auxiliary. This paper put forward the suggestions that EV charging network construction should carry on with EV development synchronization, give full play to advantages of dispersion charging, charging avoiding peak load and charge in valley load, instead of laying a large-scale charge-station network. Secondly, this paper discussed the construction and the management of charging network, focused on the network planning, charging standards, and the role of power enterprises. Finally, the pattern of charging operation and the management is chosen, three kinds of patterns are proposed to different periods and users, the centralism charging management pattern, the dispersion charging and centralism maintenance pattern, as well as the battery renting pattern.

In this paper, the Standard k- ε equation turbulence model was used to simulate three-dimensional flow over a spillway. The volume of fluid method (VOF) was introduced into the iteration of calculation to solve the free water surface, and segregated solver was used with the PISO pressure-velocity coupling scheme. The free surface, the magnitude and distribution of the velocity, the pressure on the spillway surface and so on were obtained. The simulation results were in good agreement with the experiment data.