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CAD / CAE model of plate structure is designed for plate heat exchanger provided by the manufacturer. Stamping process of the plate is simulated using Dynaform which is the special software of numerical simulation for sheet metal. The quality of plate stamping is analyzed by thinning rate, forming limit diagram (FLD) and other indicators, and compared with practical problems. At the same time, twelve levels experiments programs including ripple inclination, ripple normal pitch and ripple height are established according to uniform design principles based the parameters of ripple structure provided by manufacturer, and twelve chevron ripple plate models is established and their forming quality is analyzed with Dynaform Software. Influence and laws of plates three structural parameters, plates’ section parameters , BHF for stamping quality are studied and summarized, and the optimal choice of the plates is fond out to provide a theoretical basis for the actual production.

Stereo matching methods are widely used in computer vision and stereo reconstruction, from the perspective of improving the matching accuracy, this paper focuses on the global optimization algorithm. An improved Belief Propagation method is proposed in this paper, by involving more pixels into information transmission, our method improves the accuracy ofstereo matching. The experimental results verify the efficiencyand reliability of our method.

The research has revealed the problem of sulfur dioxide emissions during the coal combustion. Combustion experiments were made for Shanxi coal at 1000oC. Red mud, carbide and shell powder were chosen as the primary sulfur-fixing agent. Through the experiment, the best ratio of Ca/S is 2.0 at 1000oC. When the ratio of red mud, carbide and shell powder were 50%, 15% and 35%, the maximum sulfur-fixing efficiency was 76.05%. Orthogonal experimental results showed that the best additive formula was 9% of Fe2O3, 5% of Na2CO3, 5% of ZnO. The maximum sulfur-fixing efficiency reached 89.23%. In addition, it was made thermogravimetric analysis of coal with different additives. By contrast, samples with sulfur-fixing agent generated two-stage combustion significantly, ignition point increased. The amount of coal residues with sulfur-fixing agent and sulfur-fixing additives showed an increase in the quantitative analysis.

Currently, there are less online monitoring forecast methods about running condition and fatigue life of mechanical parts, and the current methods have higher false alarm rate. To solve this problem, danger theory of artificial immune system were introduced into condition monitoring methods. An algorithm to predicting the using state or fatigue life of mechanical part was proposed. In this algorithm, the definition and the generation of danger signals are proposed combined with fatigue life and reliability of mechanical parts. According to the results of simulation and experiment, the theoretically residual fatigue life and reliability calculated from simulation analysis kept accordance with the actual residual fatigue life and the real reliability. This verified the validity of this algorithm proposed in this paper.

Due to that the Doppler parameters vary according to slant and the resolution is lower using imaging algorithm of traditional pulse compression in processing raw echo data of the missile-borne synthetic aperture radar (SAR). Moreover, an algorithm is proposed to solve these problems, which is based on the fractional Fourier transform (FrFT) for missile-borne SAR imaging. Firstly, an echo signal model is built for the terminal guidance stage of the missile-borne SAR. Secondly, measure the chirp rate of the echo signal through the local optimum processing and get the optimum angles for the FrFT, and then the entire SAR image can be obtained by using FrFT with the optimum angles of the azimuth and range. Finally, the performances of the algorithms are assessed using simulated and real Radarsat-1 data sets. The results confirm that the FrFT-based missile-borne SAR processing methods provide enhanced resolution yielding both lower side lobes effects and improved target detection. The method introduced in this paper has important theoretical significance in detection and recognition for military targets and precision guidance.

Concrete structures are exposed to severe environment that may cause rapid decay, shortening their service life and raising maintenance and repair costs. Chloride ions will lead to the depassivation of reinforcing steel bars in concrete which is one of the most serious problems to the durability of concrete. Then, the prescriptive methodology is not a guarantee to obtain the desired service lives of 50 or 100 years. Surface treatment is commonly used to improve the resistance of concrete to chloride erosion. Using the silicone materials to an immersion treatment can effectively block the invasion of harmful substances,the resistance of concrete to chloride penetration with surface protection with silicone materials was evaluated. The results showed silicone can improve the resistance to chloride penetration than the non-protected concretes. As a kind of polymer materials, the aging behaviors of silane is a matter of urgent concern. Hence, the aging behavior of silane coated concrete is evaluated by the test of water absorption after 1000h xenon lamp aging, which exhibits excellent anti-aging performance of silane.

To solve the problem of early-age concrete shrinkage under constraint, 0%, 2%, 3%MgO expansion agent are mixed in the concrete. Results indicate that MgO expansion agent can ensure the expansion strain of the concrete and produce the self-stress under constraint which is up to 1.8Mpa~2.2Mpa.

The understanding of stress relaxation and tensile creep behavior is extremely important in accurate stress analysis and crack prediction of early-age concrete. The free shrinkage deformations of concrete with different strength grade were examined. The early-age tensile elastic modulus of concrete was investigated through temperature-stress testing machine. The tensile creep and shrinkage stress were obtained through the modified restrained ring test. The results indicate that the development of free shrinkage coordinates well with the inner strain of steel ring. Tensile creep decreases as water-binder ratio increases. Creep counteracts tensile stress of concrete by 28%~40% , decreases the possibility of cracking of concrete at early ages.

For intelligent distribution system including Distributed Generations, we take the generator and load static characteristic into account and propose a flexible power flow algorithm for distribution network including second-order items. First, this algorithm modifies the distribution network power flow equations including second-order items in order to meet the static characteristic of generator and load. Moreover, we use the fsolve function of MATLAB to solve the power flow equations. This algorithm makes full use of the characteristic of high accuracy of the distribution network flow equations including second-order items and good convergence of the fsolve function. Compared with conventional distribution power flow algorithm, it does not need to set the trend flexible node type of each one. Not only the voltage amplitude, phase information of each node and the system frequency information can be calculated, as well as the actual power of generator and loads. The result of the algorithm is more in line with the practical electric power system engineering. Improved IEEE33 node system is chosen to verify the correctness of the algorithm.

According to the sap flow characteristics and photosynthetic characteristics of Haloxylon ammodendron and Tamarix, we measured the sap flow with the method of thermal diffusion. To monitor photosynthesis with application the instrument CI-340, and the result shows that: (1)The daily net photosynthetic rate change of Haloxylon ammodendron is a typical double peak type, and Tamarixs is a single peak type; (2)The daily transpiration variation of Haloxylon ammodendron is similar to net photosynthetic rate change rule, it has a phenomenon which we called noon break, Tamarixs isnt obvious, it presents volatile changes slightly; (3)The daily sap flow of Haloxylon ammodendron is a typical double peak type, Tamarixs isnt obvious, it presents volatile changes slightly, and at sometimes the sap flow of branches is greater than the breasts. The results provide some supports for ecological water demand of the plants. It has some significance for ecological environment construction of the Gurbantunggute Desert.

This paper study on the permeability, start-up pressure gradient and stress sensitivity of advance water injection in extra-low permeability reservoir in Fuyu Oil layer of Daqing Oilfield. Experimental results show that the reasonable formation pressure level should be at about 120% in the advance water injection experiment, advanced water injection in the the early stage have higher oil production, the water breakthrough, earlier than synchronous water injection has certain inhibitory effect of water cut rise; Under the premise of advance water injection can overcome the start-up pressure, the lower the level of the reservoir permeability, the higher improve recovery efficiency of the proportion; permeability retention rate increase by about 22% with 5×10-3μm2 core and effectively overcome the stress sensitivity of low permeability reservoir damage; Advanced water injection can overcome stress sensitivity and restoring formation pressure, all that influence the start-up pressure gradient, which significantly reduce the start-up pressure gradient.

We used CFD method to numerical simulation of solid-liquid two-phase flow in nozzle flow inside the nozzle, simplified structure, used the RNGk-ε model for numerical simulation. Through numerical simulation, we get the velocity distribution and the erosion distribution, provide guidance for further improvement and application in structure engineering

A new burn-in test system of motor controller using zero-sequence current control is presented. The new system consists of two motor controllers and a three-phase reactor. The zero-sequence current control ensures that the three-phase current is symmetrical and sinusoidal, so that two motor controller can be tested at the same time. The results of the simulation demonstrates that the zero-sequence current control is able to ensure that the three-phase current is symmetrical and sinusoidal and can meet all the requirements of the burn-in test system of motor controller. The system uses less hardware, has less loss and it is more energy-efficient, more convenient.

Though artificial design effecting environment is supposed to be significant in environment design, we emphasized how artistic conception expression of water spray morphology expressed in environment design combining the case that Chinese Meishan cultural eco-garden landscape design. We hope natural environment factors would be more considered in future environmental design and better utilize natural environment to improve human artistic sensibilities by enhancing design environment.

In order to improve the detection performance of ultra wideband (UWB) system, a nonlinear scaling UWB pulse based on generalized Gaussian pulse (GGP) was proposed in this paper. Then wideband ambiguity function (WBAF) of the pulse was derived and analyzed to show the relationship between its range ambiguity function and nonlinear scaling characteristic parameters. The simulation demonstrate that such UWB pulse can achieve the thumbtack WBAF, low side lobes and high range resolution can be achieved by increasing modulation frequency offset and decreasing modulation frequency. The simulation result can provide theoretic guidance to UWB pulse design.

A new hydrocyclone and gas-flotation device was designed and tested for the treatment of the wash water containing the flocs. The device separates particles and removes flocs simultaneously. The gas-generator equipment can produce a large number of micro-bubbles, and the bubbles adhere to the impure flocs particles. This makes the density of the bubble-floc less than that of water, and their buoyancy enables particle separation and removal of suspended flocs. To achieve a high efficiency of flocs removal and particle separation, some of the factors that influence the separation efficiency (such as the gas-liquid pressure difference, gas-liquid ratio, underflow split ratio, water pressure, inlet flow rate, and the contact time of the gas and particles, bubble size, and number of bubbles) were investigated. The results showed that there is an optimum combination of multi-dimensional parameters; good particle separation and a high efficiency of flocs removal were achieved.

On the demand of miniaturization of antenna, this paper presents a circular microstrip antenna whose part of its port is sealed. Changing part of its magnetic wall into electric wall, then a decimals mode which exist between andis proposed. Elaborating the theory of reducing the resonant frequency with Bessel functions characteristics and resonance formula of circular microstrip antenna. Using the HFSS for simulation, the resonant frequency of the antenna change from 3.0 GHz to 1.2 GHz. The results prove the reliability of theory analysis. The size could be reduced nearly 60% compared with ordinary antenna. The antenna has a simple structure and can be applied to engineering application.

The plants' sap flow can characterize water transpiration and consumption, reflect water transmission situation and then determine the vegetation ecological water requirement. This paper takes Haloxylon ammodendron and Tamarix as the research object, adopts thermal diffusion method[1], studies vegetation trunk fluid flow characteristics and the relationship between the meteorological factors. The results show that: (1) Haloxylon ammodendron and Tamarix's sap flux density are showed obvious diurnal variation rule, there is a "nap" phenomenon. Haloxylon ammodendron's liquid sap flux density of monthly mean performance is July > June >August, and Tamarix is July > August >June. (2) Haloxylon ammodendron's flow start time in cloudy is delayed about 1 ~ 1.5 h or so than in sunny day, and Tamarix is about 0.5 h delay. (3) Haloxylon ammodendron and Tamarix's fluid sap flux density in each month are significantly related to meteorological factors, through the regression analysis, Haloxylon ammodendron and Tamarix's trunk liquid sap flux density can make a regression model with meteorological factors.

According to the suffered various impacts and vibrations of traction driving part in high-speed train under complex operating environments and conditions, the modal problems in the rotor of traction motor, power output device in traction transmission system, working in high-speed trains is investigated. In this paper, a Finite Element Analysis model for rotor modal simulation research is established, by using which the influences of structure parts on motor natural frequency is analyzed. From the simulation analysis, the natural frequencies, the vibration mode and the amplitude of each order modes are obtained, which could provide a theoretical basis for the rapid, stable and safety operation of high-speed trains.

Influenced by Le Notre Garden, Peter Walker’s works brought forward the landscape architectural modernism movement while embracing classical elements. Most of his works have geometric and symmetrical layout with axis and specifics to sites. Modern materials, dynamic and static waterscape, geometric shaped plants and sculptures are common elements of his design. This paper analyzed the innovative style and features of Peter Walker’s five modern-classical landscape works: Burnett Park (Fort Worth, Texas, USA), Garden of Kempinski Hotel (München, German), Toyota City Museum of Art (Toyota City, Aichi, Japan), IBM Solana (Dallas, Texas, USA) and Cambridge Center Roof Garden (Cambridge, Massachusetts, USA).

Fast, simple and reliable method for judging the behavioral status of video object is the public research base of many application fields, including public safety monitoring, national defense, aeronautics, sports and so on. This paper focuses on the fast parametric skeleton modeling and simple process of vectorization. It proposes an improved thinning algorithm for fast skeleton modeling and then locates the key points by a new scanning and marketing method, ultimately, according to the coordinate of the key points, it constructs a matrix of pose estimation and formulates the behavioral status judgment as a problem of calculating the angle between vectors. This method not only resolves the problems of large volumes of data and high complexity of algorithm in the traditional approach, but also lays the foundation for the extended researches and applications of multi-field intelligent video behavior analysis.

In computer vision field, video target tracking has important significance of research. This article proposed a fast and efficient multi-cameras-relay target tracking method directed at crucial technology questions in video target tracking. First, it separated the foreground and background of monitoring scene using of Markov random field theory, and then established the Markov random field model of foreground and background, so as to accomplish the moving object recognition; The next, it located the accurate positioning and tracking utilizing the combination of Kalman filtering and improved Camshift algorithm; finally, it made more-cameras-relay target tracking on the basis of coordination and synchronous between cameras, to achieve high efficiency of tracking and strong robustness and monitoring of the wide range of target real-time tracking.

The traditional process of thesis evaluation is of subjectivity and differences of teachers’ qualifications and backgrounds. Considering these characteristics, this paper proposes a multi-level theses evaluation model based on fuzzy cluster analysis with the idea of fuzzy mathematics. In this model, it evaluates the teachers’ qualification first to determine the weight of various teachers’ evaluation to the thesis; then stratifies theses evaluation indicators, and according to the results of various indicators, it builds a fuzzy equivalent matrix, and ultimately selects the appropriate similarity coefficient to divide the theses into excellent, good, moderate, bad four grades. This model greatly improves the scientificalness and objectivity of the traditional theses evaluation process and provides a reference for the process.

The study of low frequency, small size transducer was an important aspect for the development of the underwater acoustic transducer. The Class Ⅳ flextensional transducer was a typical low frequency, high-power and small size transducer. For decreasing its resonant frequency in the case of small size, a flextensional transducer with slotted shell was analyzed using finite element software ANSYS. A comparison between the flextensioanl transducer with slotted shell and the Class Ⅳ flextensional transducer was made. The maximum size of the shell is 200mm. The transmitting voltage response of the transducer reaches to 131dB with resonant frequency 600Hz in water. The transducer could radiate at low frequency with small size of the shell.

A feature selection method for manual operated directional valve based on EMD and GA-PLS is proposed. Vibration signal from a manual operated directional valve is difficult to find the main fault features. The EMD method is used to decompose the vibration signal into a number of intrinsic mode function (IMF) components. Auto-regressive (AR) model is a time-series tool which can represent the important information of system state. Therefore, AR model of each IMF component is established. The AR parameters and the loss function are regarded as the feature vectors. In order to reduce feature vectors, Genetic algorithm-partial least squares (GA-PLS) is a suitable method for selecting effective features. GA-PLS method is used for selecting new features from these feature vectors, which constitute the AR parameters and the loss function. Experimental results show that this method can be applied to select features effectively.

The hydraulic characteristics of curved channel flow are one of the most important subjects to hydraulic researchers and engineers. Among them the magnitude of circulation velocity and its calculation method is of great interests. Experimentation of generalized curved channel was carried out to explore the flow velocity parameters and circulation velocity characteristics by adopting the ADV to measure and analyze the 3D velocity datum. Theoretic formula was established for calculating the circulating velocity in the curved channel. Comparison with the results calculated from the formulas of other researchers the formula proposed in the paper is relatively quite good. The paper provides a basis to explore the hydraulic characteristics of the curved channel profoundly.

Ternary composites of Polyamide 6 (PA6), the mixture of Maleated and Unmaleated Ethylene Propylene Diene terpolymer rubber (named EPDM-M), and nanoCalcium Carbonate (nanoCaCO3) were prepared by one-step and two-step compounding routes. The toughness of the composites was tested by impact test. The microstructure morphology of impact surface and etched impact surface was investigated through scanning electron microscope (SEM). The result shows that toughness of the ternary composites with sandbag microstructure was 270 % higher than neat PA6. The SEM morphology shows that strongly elongated microfibrils and deformation are formed in ternary composite with sandbag microstructure, which cause larger shear yielding and crazes in the surrounding matrix to dissipate more impact energy. Additionally, strong ligaments are observed at the crack tip, which could promote plastic deformation and consumption of fracture energy.

Gelator (G2-C12-G2) was synthesized successfully, the structure of which was confirmed by1H-NMR and Mass spectra (MS). And G2-C12-G2was used to modify PMMA by “in-situ” polymerization. The results of gel permeation chromatography (GPC) showed that Mn and Mw/Mnof the PMMA composite were barely influenced by the incorporation of gel. The results of dynamic mechanical analysis (DMA) showed that the modified PMMA had higher modulus, toughness and glass transition temperature (Tg) than pure PMMA. Furthermore the results of spectrophotometer showed that the transparency of modified PMMA was nearly the same as pure PMMA .

Polymethyl methacrylate (PMMA)/ acrylonitrile-styrene-acrylate terpolymer (ASA) alloy was prepared via melt blending method. Effects of ASA melt flow rate and PMMA/ASA ratio on mechanical property of the alloy were studied. It showed that when the high melt flow rate ASA was used, alloy’s tensile strength and flexural strength were little different from using low melt flow rate ASA, while the impact strength was significantly higher than the latter. Differential scanning calorimetry (DSC) analysis showed that a glass transition (Tg) platform emerged in low melt flow rate ASA at 48.5°C, which represented the Tg of the interface phase formed between SAN grafted acrylate rubber particles and SAN matrix. Scanning electron microscope (SEM) experiment further showed that when low melt flow rate ASA was used, alloy’s cross section was smooth which showed the characteristics of brittle fracture.

As the monitoring subject of construction engineering investment, engineering project supervisor plays a vital role in the investment control of construction stage. Based on the research by the construction supervisor about the construction phase of the investment control, this paper combined with engineering examples, and analyzed many reasons and key points that have influenced the investment control in the construction stage, and tracked out the investment control methods and measures aimed at each point that supervisor should do, thus to control the investment cost in construction stage effectively.

In the same well water flooding process, solid particles contained in the fluid often result in the impeller submersible electric pump to erosion wear. We use Fluent software to establish the model of flow field,and use numerical simulation method to analyze the erosion wear. We use the erosion theory to calculate the erosion wear rate,and verify the correctness by the contrast between the results of numerical simulation and actual value.

Erosion is a failure phenomenon which caused by relative motion between the surface of a fluid and material, it often results in the failure of the device, affects the normal operation of equipment. This paper describes the design of a erosion experimental device combined with the characteristics of the existing types of erosion experimental advantages, disadvantages and metal material erosion experiment. The device consists of a plurality of tank, pump, spray tanks, cam nozzle, pipeline and so on. It can control to the impact velocity, impact angle.

A new kind of liquid crystalline material with an azo group in the molecular core was synthesized successfully. The chemical structures of the compounds were confirmed by mass spectrometry and 1H NMR. Their phase structures and transitions were investigated by differential scanning calorimetry. And the liquid crystalline behaviors were researched with polarized light microscopy experiments. The experimental results suggested that the compounds with a azo group in the molecular core can develop into a well-defined nematic phase.