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The application of distributed temperature sensors(DTS) to monitor producing zones ofhorizontal well through a real-time measurement of a temperature profile is becoming increasinglypopular. The information from DTS can potentially be transformed to obtain the permeability alongto the wellbore and well completion method and so on. The relationship between these parametersand the real-time temperature distribution along the wellbore is very important. Based onmass-,momentum-,and energy-balance equations, this paper established a model to predict thetemperature along the horizontal wellbore. The models presented in this paper account for heatconvective, fluid expansion, heat conduction, and viscous dissipative heating. Wellbore temperaturecurves are plotted by computer iterative calculation. In addition, this paper revealed the relationshipbetween wellbore temperature distribution and different characteristics, such as permeability alongto the wellbore and well completion method. The analysis results show that permeability differenceand different well completion methods may lead to different downhole temperature distribution atthe same time step, different production rate, different wellbore temperature as well as the change offriction factor in the wellbore. From the temperature distribution and temperature derivative curvesin different cases, we could easily derive the permeability distribution along wellbore and thelocation of the perforated intervals and the fractures.

In this paper, different SBA-15 molecular sieves were prepared in a facile sol-gel method by using a low-cost sodium silicate as silicon source at different ripening temperature. The materials were characterized by small-angle XRD, TEM, nitrogen adsorption–desorption test. The results showed that ripening temperature can affect the pore size and mesostructure of SBA-15. High surface area SBA-15 can be obtained at low ripening temperature, and plugged mesostructure can be prepared at high temperature. The gravimetric humidity sensing property of the materials were tested based on a transducer of quartz crystal microbalance. The test results revealed that all the samples showed high response in the wide range of relative humidity. The sensors based on that prepared at 35°C show a good stability and linearity in the range of 11.3%RH to 98%RRH along with fast response (12s) and recovery time (8s), ultrahigh sensitivity and low hysteresis, implying that has a great potential for humidity detection.

The aim of this paper is to elucidate the drainage gradient method's feasibility in evaluating and screening anti-scaltants. Nine different anti-scalants were selected as research object, the results show that KCa、KJD、pH and Langelier's saturation index (LSI) can be used as indicators and KJD、pH are more sutible indicators.with the relative standard deviations (RSD) of repeated experiments were from 0.24% to 3.04%, the drainage gradient method has good repeatability.

Nebkha plays a major role in the ecological and environmental stabilization by accumulating wind-blown sediments around shrubs. Grain-size characteristics of different positions on nebkha reflect the sorting effect of aeolian dynamics. Based on the collected sand grains of different positions on four types of nebkhas at the southern fringe of Taklimakan Desert, China, this paper provided detailed insight into variability of the grain size of surface sand on nebkhas. The results showed that: a) Grain-size distributions on shield-shapedKarelinia caspica Nebkhasunder natural condition had the larger spatial variability in comparison with the others. b) Grain size on nebkhas regularly showed the spatial variation. Grain size was increasingly larger along the windward slope upward, and then became finer along the leeward slope downward. c) The grain-size sortings of different positions on shield-shapedAlhagi sparsifolia Nebkhasunder new reclaimed land were the best.

Network security assessment is a complex multi-criteria problem including both quantitative and qualitative factors. In this paper, taken the computer network security evaluation index for a research object, the judgment matrix of index weight was improved based on the fuzzy theory, and a new weight determination approach was proposed to make up the shortcomings of traditional weight determination method and highlight the fuzziness of expert judgment. Meanwhile using fuzzy theory to establish fuzzy evaluation matrix, then combine analytic hierarchy process to set up a fuzzy AHP evaluation model of the computer network security. At the final stage, a security assessment of the system of an institution’s network was to implement to demonstrate the feasibility of the evaluation model.

Since twentieth Century 40's, some foreign enterprises in developed countries began to study and produce sweeper [1-2]. Research on China's sweeping car began in twentieth Century 60 years, but until the 80 time end when china had been reforming and opening that it began to rapidly develope [3-4].But the study of mouth has the same general trend at home and abroad. Due to the different design of suction mouth, circulation type pneumatic conveying systems in general can be divided into open pneumatic conveying system using pure suction type suction mouth [5] and the use of reverse blowing type suction mouth delivery system [6]. Now most of the sweeper adopts the latter, but if the back blowing type suction mouth design improperly ,it can not achieve the ideal effect of absorbing dust, and may lead to strong fugitive dust [7-9].Today although road sweeper have been studied for decades at home and aboard, but these studies mainly is through the enterprise using engineering practice means to complete ,there are two situations occurring as follows: a number of technical on research and development need to rely on our own to explore; The engineering practice have greater demand for human, material and financial resources, and it is difficult to achieve better expected. In order to solve the problems of the above two points, according to the fluid mechanics analysis, this paper mainly research and analyze the sweeper suction mouth's flow field pickup role of entrainment process for particulate contamination by negative pressure suction, which can provide a foundation for the research and optimization of sweeper pneumatic conveying system.

In this paper, the 3D flow analysis model of gasoline engine turbocharger compressor was built by using the software NUMECA. The flow fields of the vaneless diffuser and volute, such as airflow velocity field, temperature field, pressure field and the entropy field were simulated. The internal flow performance of the vaneless diffuser and volute were analyzed. The simulation results show that the field changes accord with the compressor characteristics, thus the vaneless diffuser and volute of the compressor design is reasonable. The approach of numerical simulation and flow field analysis by using CFD method can accurately predict the compressor performance. The research methods and conclusions provide theoretical and practical reference for the optimization design of the compressor.

Antibacterial layer was prepared on the aluminum surface by anodizing pure Al and electrodepositing Cu in the pores of the anodic aluminum oxide (AAO) membrane. The AAO membrane was generated by a two-step anodization process in oxalic acid solution. The electrodeposition of Cu was conducted in copper sulfate solution using alternating current. The structural characterizations by scanning electron microscopy (SEM), X-ray diffractometer (XRD) and energy-dispersive spectrometer (EDS) show that Cu nanowires with an average diameter of 70 nm are assembled in the pores of the AAO membrane. The tests of antimicrobial properties against two typical bacteria of Escherichia coli (E. Coli) and Staphylococcus aureus (S. Aureus) indicate that surface antibacterial layer of aluminum possesses excellent antimicrobial properties and the maximum value of the antibacterial rate can reach 99.9% both for E. coli and S. aureus.

On the basis of thermal measuring method, a hot-film gas flow sensor is proposed. Its sensitive element is a FS5 probe, which is integrated with measuring resistance and temperature compensating resistance inside. In order to achieve temperature compensation, the main measuring circuit is designed. Considering minimizing errors in this circuit, the temperature correcting circuit is added to further modify output voltage. By fitting measurement data of gas flow and the final output voltage with least square method, an operating characteristic curve is obtained as well as its 4th order polynomial. Under equivalent conditions, the proposed sensor, a high-precision standard sensor and an industrial sensor are experimented upon and the contrast analysis of their measurement results is given. The experimental results prove that the proposed sensor has high precision with measurement error less than 3%. Therefore the proposed sensor is feasible for industrial applications.

Combining high thermal conductivity and high latent heat of phase change Materials (PCM) with heat pipe that has strong ability of heat transfer. A three-dimensional transient heat-transfer model was set up to simulate the temperature distribution in the lithium-ion battery under different conditions of heat generation rate and different ambient temperature. The study revealed that composite cooling system keep the battery temperature below 40.2°C on average working condition, the highest temperature was not exceed 48.7°C even under stressful conditions. However, use PCM without heat pipe as cooling system, the temperature was 2~6°C higher than composite cooling system at the same condition. The composite cooling system was superior to PCM cooling system, especially in high heat generation rate and high ambient temperature.

This paper discusses a selecting method of Reserve Osmosis (RO) scale inhibitors, which is fast and convenient. Five kinds of RO scale inhibitors (A-E) are used to explore the feasibility of the method, drawing their conductivity titration curves to evaluate their properties. The results show that, using the rapidly-dropping point of the conductivity titration curves to select the RO scale inhibitors can illustrate the preferential order of the scale inhibiting properties is B≈E>D>C>A.

In addition to be used in the manufacture of tires, rubber is also widely used in the preparation of sporting goods. In table tennis, the rubber is used in the manufacture of the rubber on the table tennis bat that it can satisfy the requirements for high elasticity and durability of the bat. With the continuous development of table tennis, and increasingly fast ball, rotating become stronger and stronger, this calls for increasingly high quality and specifications of the table tennis equipment. The table tennis bat is composed of three parts, the bottom plate, rubber and sponge, the reasonable collocation of the three determines the quality of a bat. The physical properties of table tennis pat rubber has a great influence on the quality of a bat, with regard to the production of rubber products of table tennis pat rubber, on the basis of choosing the appropriate types of rubber, by adjusting the rubber compounding and production process reasonably, that the products with the best performance can be obtained.

With the continuous progress of science and technology, especially with the continuous development of material science, many new materials are applied to all kinds of sports equipment and equipment. It boosts the irreplaceable role for the development of competitive sports. This research is on the carbon fiber material model in the tennis racket on the application of analysis and discussion. The systematic study is on the characteristics of carbon fiber materials, to provide the theoretical basis for the application of the present sports equipment development of carbon fiber materials.

A novel method for the catalytic oxidation of o-chlorotoluene (OCT) to o-chlorobenzaldehyde (CBD) was proposed using vanadium doped anatase mesoporous TiO2 (V/MTiO2), the catalytic reaction conditions were investigated. Under the optimum catalytic reaction conditions: 10 mL of acetic acid 100 °C of reaction temperature, 10 h of reaction time and 100 mg of catalyst, the conversion rate of OCT could reach to 95.3%, with a selectivity of 63.5%.

The rigid-flexible coupling model of wind turbine was established in ADAMS to study the vibration characteristics, which was based on the working principle of megawatt wind turbine. The natural frequencies and vibration modes of the tower have been obtained by dynamic simulation analysis and vibration analysis of the wind turbine. The comparison of the first-order bending natural frequency by raley analysis algorithm and the first-order bending natural frequency by the software, which has validated the correctness of rigid-flexible coupling model of wind turbine, the analysis of vibration characteristic has verified the rationality of the structure of the wind turbine.

A cross-platform software application was developed to manage energy generation and consumption intelligently in smart homes. The system model consists of domestic loads, household distributed energy resources and an energy storage component that supports scheduled charging/discharging. The software deals with all these electrical devices as well as their energy information, based on which real-time conditions are presented to the resident and the history can be queried. Whats more, the application fulfills kinds of energy profiling and pricing-related optimization on account of demand response, resulting more monetary benefits and comforts. The software interacts smartly with energy owners by graphical user interface (GUI) and enables an intelligent electricity usage pattern in the context of smart power consumption within the framework of smart grid.

Mesoporous TiO2 with anatase crystalline structure (MTiO2) has been synthesized by using Lac Red as template. The synthesized mesoporous titania samples were characterized by a combination of various physicochemical techniques, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM), N2 adsorption/desorption. It was found that without any external doping MTiO2 exhibited significant high adsorption abilities for adsorbing the gaseous acetaldehyde by the adsorption ratio of 39.15%.

Cerium-doped microporous-mesoporous composite material (Ce-M-M) was synthesized by the hydrothermal method. Ce-M-M was characterized by N2adsorption-desorption and FT-IR. The results showed that the Ce-M-M has composite pore structure combining both micropores and mesopores, and the pore sizes are mainly located at 1.7 nm, 2.3nm and 2.7nm. The specific surface area of the Ce-M-M was 1288 m2g-1with a pore volume of 0.66 cc/g. In addition, NH3, a harmful component in cigarette mainstream smoke could be effectively reduced 66.9% by using Ce-M-M as an adsorbent.

The 3D model of bolt connection between flange and yaw gear was established in Pro/E and pre-processed in Hypermesh. Then build the contact model of bolts in ABAQUS and analyzed the statics performance by taking different preload in two kinds of working condition, which stimulated the preload and limit load condition. The results show that, through comparing the stress strength under different preload condition, the author puts forward a value range of preload for reference: Fv = (0.6~0.8) AS · σp0.2. The research provides a reference for strength check, fatigue analysis etc. of the bolt connection on yaw gear of the MW wind turbine generator system and other bolt connection systems, to facilitate further optimal design.

There are a lot of harmful components which is carcinogens in cigarette mainstream smoke, especially the ammonia, phenol and crotonaldehyde. The adsorption of ammonia on Al-Ca-SiO2 composite material was carried out in a batch home-made slurry-type reactor system. And the material was characterized by N2 adsorption-desorption and FT-IR. The results examined by Hongyun Honghe Tobacco (Group) Co. Ltd. reported that the Al-Ca-SiO2 has a high effect on the adsorption of ammonia (16.8%), phenol (10.3%) and crotonaldehyde (11.2%).

The visual and simulated system of the orbiting satellite based on the OpenGL technology is designed and realized in this paper, in which a visualization platform of the satellite in-orbit running is constructed. The simulation system has constructed the satellite model and the earth model by making use of 3DS MAX technology, and achieved the visualization of satellite in-orbit-running, the visualization of the communication route and of the overlay effect. At the same time, which has realized the access to the database of the orbiting satellite by means of ADO technology .The practices have proven that the system can simulate the whole process of satellite in-orbit-running in real-time, and provides the assistant support platform of the real-time management and decision. Apart from this, the system provides the network training of the space forces with virtual training platform. It is of great significance to construct the virtual battlefield simulation system.

Mesoporous cobalt doped aluminium oxide (Co/MAl2O3/RL) was synthesized using rubber latex as biotemplate by hydrothermal method. The synthesized mesoporous aluminium oxide samples were characterized by a combination of various physicochemical techniques, such as X-ray diffraction (XRD), N2adsorption/desorption and Fourier transform infrared (FT-IR). Espciallly, Co/MAl2O3/RL exhibited a high efficiency of acetaldehyde adsorption from mixed gaseous mixture.

To overcome disadvantages of complex wiring and difficult maintenance for traditional wired sensor networks, a data acquisition system for chemical equipment monitoring based on wireless sensor network has been put forward. The proposed data acquisition system has functions of real-time data acquisition, transmission, storage, query and remote sharing of history data, and provides favorable technical supports for real-time chemical equipment monitoring. First, the system framework, EMBV210 hardware are introduced. Then, in the LabVIEW platform, the data acquisition system is developed, and the remote sharing of equipment operating status by DataSocket is realized. Finally, the proposed data acquisition system is simulated and verified. The work provides a feasible way for chemical equipment monitoring and useful references for the development of other similar integrated measurement and control systems.

In order to eliminate the measurement error caused by working voltage fluctuation of weighing sensor, a dynamic voltage compensation method for improving the weighing accuracy was proposed in the paper. The method takes strain gauge type pressure sensor as the weighing sensor and corrects Wheatstone bridge circuit. By synchronously detecting output voltage signal and working voltage of the weighing sensor, the method dynamically compensates the working voltage fluctuation of the weighing sensor, corrects the measurement error caused by the voltage fluctuation of external source and calculates the weight in real time. A weighing system based on the digital signal processor (DSP) was designed. Results of simulation experiment verify the feasibility of the proposed method.

To reveal relationship between water content of plant tissue and soil moisture in the hinterland of Taklimakan desert in China's southern Xinjiang, Haloxylon ammodendron and Nitraria sibirica were selected, and the water potential and content in the tissues of two plants under drought stress were determined. The results were shown that: (1) water potential in the morning and the water content in the tissues of Haloxylon ammodendron and Nitraria sibirica decreased with the decline of soil moisture content. (2) When the soil water stress appeared, the water potential values of Haloxylon ammodendron and Nitraria sibirica were -4.47 MPa and -5.88 MPa, respectively. (3) The lower limits of soil moisture contents that were suitable for the growth of Haloxylon ammodendron and Nitraria sibirica were 2.50% and 3.00%, respectively.

Limitation of water resources at the arid countries (Uzbekistan and the most part of the Chinese national democratic republic) demands to develop more exact and mathematically proved methods for moisture management on an irrigated field. Results of theoretical researches on dynamics of humidity have shown: (1) similarity of physical processes of change of humidity of soil on different irrigated areas. (2) Hysteresis of the nature of humidity at an irrigation and drainage. (3) Sharp recession of humidity of soil in the root zone.

In the process of deep etching of silicon, the metal film or the oxide film served as silicon protective layer needed to be etched before using plasma etching technology. In order to solve the etch rates variance of different aperture sizes and different pitchs periodic patterns, by controlling the water bath temperature and etching time, the etch rates of different aperture sizes and different pitchs periodic patterns at 50 degree centigrade had been developed. Also we contrasted the etching results at different bath temperatures and got the controllable and suitable wet etching bath temperature 50 degree centigrade. At last, the paper further explores the effects of feature size and the wet etching bath temperature on etch rate.

Carbon dioxide is major cause of the greenhouse effect which is believed to be warming the Earth’s climate, the balance between accumulation of soil organic matter (SOM) and its loss through microbial respiration has global implications. In our study we have investigated dynamics of SOM during 2003-2011. Field investigations were conducted at two fields: fallow land and land cultivated by Tamarix. The following soil chemical properties also were evaluated: pH, electrical conductivity (EC), total and available NPK. The results revealed that amount of nutrients in soils are varied within two fields.

SUSXM7 Cu-bearing austenitic stainless stee1 was conducted with special antibacterial heat treatment and antibacterial properties of the steel were studied. The experimental results show that a suitable amount of ε-Cu phases can precipitate from the matrix of SUSXM7 steel after solution treated at 1100 °C and aging treated at 650 - 850 °C. ε-Cu phases are granular with diameter of 100 - 200 nm. SUSXM7 Cu-bearing austenitic stainless steels possess excellent antibacterial properties. Antibacterial rates against two typical bacteria of Escherichia coli and Staphylococcus aureus surpass 99.0％ and are basically equal to that of Cu-bearing austenitic antibacterial stainless steel researched widely now.

Based on the knowledge to defects and advantages of traditional ingot casting, a new approach for casting of aluminum alloy ingot, based on heat conduction by rotating heat pipes, is put forward in this paper. Different from the conventional casting method that cooling around ingot, the microstructure and properties of casting ingots can be significantly improved due to cooling of molten liquid from the central by rotating heat pipes proposed by this paper. Through simulation on the working process and the fields of flow and temperature, it can be speculatively seen that the ingot solidification is from inside to outside and that inner stress inside the ingot is compressive. The influences of speed of heat pipe bundle, casting speed and casting temperature on the temperature field in the ingot have been systematically studied. The ingots with different sizes can be prepared by changing size and structure layout of the heat pipes.

The data processing of cutting force is the key and basis to study various parameters of high-speed milling. To be able to read and process data quickly and accurately, especially for amounts of data lines, the researchers developed a data processing software (DPP--Data Processing Program) in high-speed milling with the use of advanced object-oriented C # language and Matlab software interface technology. After introducing the DDP, the paper also summarized and analyzed the application strategies, which can provide evidence for data processing under similar conditions.

In order to reduce effectively the particulate ignition temperature of Diesel Particulate Filter containing MnOx-CeO2 catalysts，the physical and mathematical calculation models of MnOx-CeO2 catalysts were established on Diesel Particulate Filter，and according to bench tests, the activity measurements of the five different concentrations were processed for MnOx-CeO2 catalyst. The results indicated that when concentration is 20ppm, the ignition temperature can be droped about 105°C, activity measurements of Kp、Kpm and ΔKp decrease 10%, 8% and 7% respectively. Meanwhile, regeneration time can be shortened to 7min. It shows that Diesel Particulate Filter which contains concentration of this type not only has higher regeneration rate and level , but also decrease effectively exhaust back pressure.

The Web database's classification is the key step which integrates with the Web database classification and retrieves. The traditional search engine is unable to correct search for the magnanimous information in Deep Web hides. This article has proposed one kind of classification based on machine learning's web database. The experiment has indicated that after this taxonomic approach undergoes few sample training, it can achieve the very good classified effect, and along with training sample's increase, this classifier's performance maintains stable and the rate of accuracy and the recalling rate fluctuate in the very small scope.

As a new type of Doppler wind radar, Wind profiler radar often suffers from a variety of meteorological factors. These interferences have great effect on the detection data precision, which leads to radar data quality problem. A data processing method based on Extended Kalman Filter (EKF) is presented in this paper, which focuses on the nonlinear problems of wind data of wind profiler radar. This method is the development of traditional Kalman Filter (KF) in practical engineering applications. To verify the validity of this first-order EKF from different situation, one day’s and one moment’s wind data are selected respectively, as examples for filtering. EKF is better for data processing of wind profiler radar and has some engineering application prospects.

Vegetation cover in the upper reaches of the Yellow River basin and its relation to climatic changes were analyzed at one-month resolution, using AVHRR NDVI data and meteorological records from 1982–2006. Major climatic factors that affected vegetation changes in different regions of this basin were investigated. Correlation analyses revealed that high temperatures favored plant growth in most regions, especially the southern part of the study area (regions with alpine characteristics) during early and late periods of the growth season (i.e., relatively cold periods). Increased rainfall during spring had a strong positive effect on plant growth in the eastern and northern parts (semiarid regions) of this area. In contrast, increased spring rainfall had a negative effect on plant growth in the west and south (regions with abundant rainfall but insufficient thermal energy).

In this paper the Fisher information of Gaussian pure States is studied. Based on the definition of joint non-classical properties, we calculate the non-classical properties of Gaussian pure States. The results show that the Fisher information and Fisher length are efficacious tools to study the non-classical properties of quantum States.

Ultra-thin Titanium foil, which is widely used in manufacture of thin-walled titanium tubes, automobile parts, medical and other industrial fields, is an excellent structural material. Micro-plasma arc welding system which was developed independently by Shanghai University of Engineering Science was used in the experiments of welding Titanium foil 0.05mm thick. Welding experiments were carried out with matching parameters including welding current type, welding current value, pulse frequency, ratio of peak value and base value of pulse current, amount of lap and the other welding process parameters set constant, achieved one side welding both sides formation and got good welding formation. Based on these experiments, influences on welding quality induced by those factors are analyzed.

Dust supply is important to sandstorm occurrence as well as wind regime. Dust supply is closely related to groundsurface conditions showed by these index soil physical composition, soil moisture, vegetation cover, human activities. The physical conditions of groundsurface in the Tarim basin is distributed in a ringlike pattern. From edge to hinterland, there are various landscapes in turn as follow: mountains, piedmont pluvial and alluvial fans and plains and shifting desert. At the same time, in this turn, different types of soil has been developed there: brown desert soil, ancient oasis cultivated soil (anthropogenic-alluvial soil), swamp soil, desert forest meadow soil, paddy soil, saline soil, takyr soil, shifting sandy soil, and so on. Through comprehensive analysis, some conclusions were drew as the follow: (1)shifting deserts are the major dust source of sandstorm occurred in the hinterland and the south fringe of the Taklimakan Desert; (2)cultivated soils are another dust source of sandstorm occurred in oasis areas disturbed by high-intensity human activities; (3) gobi deserts in upper of piedmont pluvial and alluvial fans and desert forest areas on alluvial plains are the potential dust sources with high dust-emitting ability that can be activiated by human activities.

Four types of heat sources of a dynamic lithium-ion battery (LIB) during charge were studied, and temperature distributions inside the dynamic LIB caused by the four kinds of heat generation sources with different currents and temperatures during charge were simulated by using a electrochemical-thermal three-dimensional model. The ohmic heat is the largest heat resource with about 63.5% in the total heat generation during regular charge, the electrochemical reaction heat is dominant when the SOC is below around 10%, and the subsidiary reaction heat can not be ignored when the temperature in the battery is above 80°C. Current as well as ambient temperature plays a very important role in the overall thermal behaviors of the battery.

A relative full-scale numerical simulation has been conducted on oscillating heat pipe(OHP) with single passageway(S-OHP)and double passageway(D-OHP). Mathematical model for studying the influence on the heat transfer performance of the number of passageway was built, including turbulence model, volume of fluid model, continue surface force model, and heat and mass transfer model caused by phase change, and all of which were based on the consideration of gas-liquid interface, wall adhesion angle, surface tension and process of phase change. Results showed that, on the one hand, strong coherence of the initial gas-liquid distribution, as well as the flow phenomena during boiling stage, were found between S-OHP and D-OHP, on the other hand, the heat-transfer capability of the D-OHP is slightly higher than the S-OHP.

In this paper, it introduces the work principle of abrasive waterjet polishing (AWJP) and analyzes the jet distance to the influence of the AWJP under a certain pressure, with a numerical simulation and analysis to the jet distance based on jet mechanics and fluid dynamics. By establishing the physical models of the different jet distance of the AWJP and adopting the Realizable k-ε model and the SIMPLEC algorithm, it gains the jet flow field of the AWJP with different jet distance models and the distribution of turbulence intensity and pressure and velocity on the workpiece surface. The numerical simulation results of the different jet distance were analyzed and compared, according to the AWJP to the characteristic requirement of the jet. By doing the polishing experiment with a abrasive waterjet cutting machine, it verifies that the best polishing distance range of AWJP is from 10 times to 13 times of the nozzle diameter, which provides the theoretical basis for the process research of the AWPJ in the future.

According to the operation condition of megawatt wind turbines yawing reducer, an assembly model of megawatt wind turbines yawing reducer is established, and aiming at different load conditions, the tooth surface of three teeth planetary gear model is analysised with using finite element analysis software-ANSYS ,including three-dimensional nonlinear contact analysis and structural finite element analysis which simulates contact stress of engagement pairs during the operation process of planetary gear. The results indicated that when the torque is M1=100N·m, the maximum stress on the engagement pairs is 177.584MPa; when the torque is and M2=300N·m, the maximum stress on the engagement pairs is 329.607MPa, which were less than the yield limit of planetary gear materials, but it can meet the design and operation requirements of planetary gear of megawatt wind turbines yawing reducer.

A finite element method (FEM) analysis based on COSMOS study with the aim to find the causes and effects of deformations in the interface between the rear axle housing and the central gear house of the four-wheel farm transporters during operation has been performed. The present design is analyzed with the aid of a mixed-fidelity, or mixed-grain, FE-model. Boundary conditions are defined on the bushings in front of the rear axle and on the air bellows behind the rear axle. The different load scenarios are represented by forces either on the wheels, the central gear or on the rear axle housing. The simulated results showed that with the worst combined load case for the different proposed design solutions suggested that modified design with a thicker flange and a removed stiffener would be significantly better than the present design; the simulated max displacement is about 0.5 mm and satisfied the design requirement. It indicated that the proposed method of finite element analysis was a good and efficient method predicts the oil leakage of rear axle housing, which can increased the knowledge of how oil leakage from the rear axle central gearbox can be controlled by design measures.

On the basis of analyzing the typical operating conditions of a vehicle model, 3D model of the rear axle housing was formed by using the Solidworks software, and the stress, strain and the fatigue life of the housing were obtained by using of Cosmos software with the method of finite element analysis. In the effect of alternating stress, the rear axle housing was found existing crack defects. The results showed that the rear axle housing life cycle was improved to over 5.0×105 and satisfied the design requirement. Results provided from tests were compared with the analyses also. It indicated that the proposed method of finite element analysis was a good and efficient method to predict the fatigue life of rear axle housing, which can provide reference for the design of that rear axle housing.

Monostatic surface wave radar is vulnerable by the threat of stealth targets and establishment of near space bistatic radar is the most achievable way to solve this problem. The positioning principle and accuracy in near space bistatic radar is discussed in this paper. The geometrical dilution of precision expression of single measurement subset is calculated. The position precision contours of measurement subsets are obtained and which subset can be chosen for positioning at different area is pointed out. Simulation results show that different subset has different position accuracy and a high accuracy subset distributing picture is presented. Research of this paper provides a theoretical base of detecting and tracking for near space bistatic radar.

Carbon fiber powder (CFP) instead of the traditional glass fiber (cloth) was used to reinforce epoxy resin for rapid tooling. There are two obvious advantages: one is to utilize the waste materials, which is good for the protection of the environment; another is to simplify the producing process by cast molding. The filling amount and dispersing process of CFP was studied in this paper. The results show that when the amount of CFP was 10 wt%, and the ultrasonic time is more than 15 min, the CFP can be dispersed in the epoxy matrix uniformly, and the mechanical properties can meet the requirement of epoxy molding.

Nitrate is one of the major nitrogen forms absorbed by plants. Dual-wavelength Ultraviolet Spectrophotometry (DUS) is a simple, rapid and environmental method to measure soil nitrate. In this study, DUS as well as Phenol Disulfonic Acid Procedure (PDAP) were adopted to analyze nitrate in five types of soils in China. It was showed that the concentrations of soil nitrate determined by DUS were higher than those by PDAP. Meanwhile, these two series of measurements were significantly correlated. Therefore, the DUS is worthy in rapid detection of soil nitrate.

The ship facilities didn’t be constructed in step with the construction of Dahua Terminal in Hongshui River of Guangxi province, while the argumentation didn’t be carried out when navigation lock was built out. In the condition above, when the navigation lock was completed, the navigation flow conditions in the entrance area of downstream and the linkage section was bad, so ships were difficult to enter the approach channel. The research of navigation flow conditions and nay navigation mechanism in the entrance area of downstream and the linkage section in current condition was implemented through physical model combining ship model. The method of using traditional navigation wall and navigation pier to improve flow conditions didn’t be adopted in renovation research. The new renovation idea of changing inflow conditions was used innovatively and bad flow pattern problem was solved by using deep pools terrain in the entrance area of downstream. After the implementation of the engineering, nay navigation problem was solved effectively and ships could pass the terminal successfully. This engineering provides a new way to solve similar terminal navigation problem.

In order to make sure a high-accuracy and fast- speed survey, a Soft-sensing model for the roughness of machining surface was built based on the support vector machines using rotate speed n, feed peed vf, and depth of cutting as independent parameters, taking groups of actual machining experiment data as samples.The allowable error ε and the positive aligned c and the kernel function parameter r were optimized by an adaptive genetic algorithm. After being optimized 300 steps, the following results can be gained through the training, testing and application. The average relative error tended to saturation training was 4.0%; the test error was less than 2.6%; the average relative error between the Soft-sensing value for the roughness of machining surface under the numerical control and the test value of the profile and roughness tester for the SV-C3000 super surface of was ranging from 0.4% to 1.25%.