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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.

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.

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.

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.

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 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.

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.

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.

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.

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.

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%.