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This paper mainly introduces the variable cross-section rotary dynamic seal, sealing mechanism, research and development, listing examples of variable cross-section rotary dynamic seal applied in the petroleum machinery. Due to its simple structure, reliable sealing performance, it is widely applied to the occasions such as high pressure, in suffering much, shock vibration.

The rotary control orifice, in which the relative angular openings are adjusted by the rotary motion of the spool, thus controlling the flow area and the flow passing through, is a basic control element of hydraulic control valve. It has several advantages, such as little minimal steady flow rate, good anti-contamination, small driving power, small opening and shutting shock, and etc., over the translational control orifice. The working medium is tap water. A model is developed and numerical studies are carried out to investigate the hydrodynamic characteristics of the rotary control orifice, including flow and pressure field, flow characteristics, flow torque. The relationships between the flow and the pressure drops, the efflux angle and the angular openings, the steady-state flow torque and the pressure drops as well as the angular openings are obtained. The results show that a) the orifice geometries have great effects on the efflux angle and the steady-state flow torque; b) Under the same openings and flow direction, the efflux angle is almost constant under different pressure drops. It is larger for meter-in flow than for meter-out flow and decreases with the increase of openings; c) The steady-state flow torque (including meter-in flowTsfinand meter-out flowTsfout) is proportional to the pressure drops and first increases and then decreases with the increase of openings, finally reaches zero at the fully opened position; d) The friction moment is proportional to the rotary speed so as the transient flow induced moment to the rotary acceleration. The in-depth study of the drag moment of rotary control orifice helps to design high performance rotary servo valve for robots. The in-depth study of the rotary control orifice provides a basis for developing high performance rotary control valve.

In this paper, MgSO4:Dy,MgSO4:Tm and MgSO4:Mn phosphors are prepare by high temperature solid state reaction. The MgSO4:Dy or MgSO4:Tm powder are mixed and sintered with MgSO4:Mn respectively to obtain the co-doped MgSO4:Dy,Mn and MgSO4:Tm,Mn phosphors. The 3-dimensional thermoluminescence spectra of these two phosphors under different sintering temperature are measured.Results show that when the sintering temperature is below 800°C, Dy, Tm and Mn ions emissions are independent. However, when the sintering temperature was over 800°C, the emission peak of Mn becomes weaker, and so do the low temperature peaks of Dy and Tm, while the high temperature peaks of Dy and Tm become stronger. This indicated that the defect complex structure in the formation of the thermoluminescence material depends on the sintering temperature. As the sintering temperature rises, more and more Mn ions combine with the rare earth ions. Therefore, the luminescence process of the energy transfer of Mn ions to the rare earth ions can be observed and the suppression to low temperature peaks of Tm and Dy, and also shown in spectra.

In order to improve precision of underwater terrain aided navigation and make full use of the features of topographic information, an analysis method is proposed in this paper, in which the variation function is used as the measurement tool. We discuss what to explore relation between variation function and underwater terrain. Through fitting experimental variation function curve, the relationships of different directions of variation function to terrain information capacity are confirmed. Meanwhile, the analysis reveals that the matching area of underwater terrain aided navigation. The experimental results show that variation function reflects the spatial correlation of underwater terrain and the features of terrain. Then, the best entering direction of matching area is found. The certain theory proofs for selection about matching area, study of the terrain adaptation and route planning can be provided.

This paper gives a detailed discussion about the gain ripple effect. Using gain equalization to compensate for the gain ripple and improve the working band of the Linearizer-TWTA system is proposed. A Ku-band equalized RF predistortion linearizer for linearizing the distortion effects of travelling wave tube amplifiers (TWTAs) is proposed. Per-tone and two-tone test experimental results show that the equalizer has improved the working band of the predistortion linearizer. A minimum of 4 dB of AM-AM improvement is made within the whole bandwidth of the TWTA, with a 20° phase shift improvement. And the maximum C/IM improvement after equalization is 3.5dB.

According to the fact that it need several tests to determine the size and motion parameters of the flapping-wing aircraft in the development processes, the paper proposed a design scheme of flapping wing system experimental platform. Separately from the scheme, the system platform, driving mechanism design, motion parameters change, described in detail the design and implementation of this innovation experiment platform. Users can simulate and debug the platform system to determine the performance of the flapping-wing mechanism.

With the development of the society, the study of folk craft and protection still appears imminent. We not only should attach importance to and protection of folk art, and to look for more advanced and effective means of protection. On the protection and development of national folk craft, directly involved in the sustainable development of national culture. Using the digital technology can realize the collection and protection of the folk craft. In this paper, under the background of digital folk craft as the research object, the digital protection of folk craft key technology and related application problem discussed in this paper, aimed at to protect, inherit and carry forward the near extinction of folk cultural heritage to provide the reference.

This paper studies the attack method in the condition of the torpedo noise covering the target noise with the help of calculation azimuth guidance. To verify the effectiveness of the scheme, the paper does simulation calculation. The simulation results demonstrated that the effect is good and the scheme haves usage value.

The paper introduces the way of solid modeling and wire frame modeling, described modeling ways from drawing the general outline of the form, to using the general model to make out the general modeling of form, to making the whole effect of the animation by combining with concrete examples which are pf rapid and convenient application value in promoting design speed, enriching expression effect (surface modeling), optimizing design process. It is beneficial to play the design wisdom, give consideration to both economic and social benefits. Its modeling is easy to meet consumer demand for fresh and exaggerated things, and helps to clear the market demand, good commodity modeling and its industrialization prospect.

This paper studied the characteristics of the bimorph piezoelectric vibrator for piezoelectric pump. By simulating the working conditions of the vibration in the pump, we constructed a dynamic model and derived the bending vibration equations of the piezoelectric vibrator under different support conditions. Then the analysis of finite element simulation is carried out for the equations, through which the vibration mode of the multi-order modal of the piezoelectric vibrator was acquired, and the relationship between the deformation deflection and peripheral support stiffness of the piezoelectric vibrator was analyzed. Finally, the deformation of the piezoelectric vibrator was tested. It is found that the test results are consistent with the conclusions of the finite element simulation, which provides a theoretical basis for the optimal design of the bimorph piezoelectric vibrator.

Most home electric appliances have standby energy waste when they are at idle mode. This standby energy is about 3% to 11% of total household electricity consumption. For several millions of households in Taiwan, this standby energy would cause billion dollars of waste per year. Therefore, in this paper we propose a standby-energy-saving socket using a microcontroller unit (MCU) to reduce the standby-energy waste. The user can start up this standby-energy-saving socket to supply power to appliances through the appliances infrared remote control or the button on the socket. When the appliances enter into the standby mode, the current sensor in the socket automatically detects it and the MCU turns off the power through a relay to reduce the standby power to zero. Based on the test, the MCU in the proposed standby-energy-saving socket only consumes about 3 mW when the socket is at sleep mode, 6 mW at working mode. The cost of this proposed socket is $9. The standby-energy saving tested on a PC is reduced by 99.93%.

Starting from constitution of design symbols, this article analyzes the constitution forms before sending and receiving messages, the decomposed information carriers of senders and receivers, the coding rules of sending messages formulated by senders and decoding rules of receiving messages by receivers, thus concludes three basic rules, namely, regular、irregular and mixed type of understanding. And the design symbol reveals the distribution and enjoyment of culture. Without social relationships and communication of individuals, there will be no symbols and transmission、the systematic integration of various human design symbols as well as the approaches of the accumulation of collective experience and the pass of behaviors of individuals.

Based on transmission model 6S, this paper uses the moderate resolution imaging spectroradiometer (MODIS) data combined with a new aerosol business inversion algorithm, V5.2 of NASA ,to retrieve the atmospheric aerosols optical depth. We take MODIS data in Shandong province as the research data, select 8 groups of MODIS LIB data set combined with Sunny weather (Sunny and cloudless or thin cloud) and AERONET release detection date (NASA release the date of detection value), and validate the retrieved results with the aerosol optical depth (AOD) of the solar luminosity observations erected by AERONET. The results show that the V5.2 inversion algorithm results and observations presented the same change trend. The retrieved results are nearly close to observed value, and the V5.2 inversion algorithm has better application in aerosol optical thickness retrieval.

In this paper, we demonstrate a novel receiver in visible light communication system based on RGB LEDs. It contains three major parts the collimating lens, the spectro-device and the photodetector. The mixed RGB signal lights are captured, separated and received by the collimating lens the spectro-device and the photodetector respectively. Through the adjustment of the collimating lens, the receiver can receive enough light even if the distance between the signal light source and the receiver is changed. The receiver has the advantages of strong mobility and strong ability of receiving signal light. Based on the designed receiver the high-speed visible light communication system using RGB wavelength division multiplexing technology can have better performance.

In order to obtain the sheet metal anisotropy under wide strain range, plane strain compression method with laminated samples is investigated. In the experiments, two laminated samples are introduced, sample 1 is deformed at rolling and thickness direction, and sample 2 is deformed at rolling and transverse direction. In the paper, the ratio of deformation forces obtained from sample 2 (p2 ) to sample1( p1) is used to assess the anisotropy of sheet metal, and verified by analytical method. The results show that the ratio of p2top1 is the function of anisotropic index r, and the anisotropic assessment by this method has a good agreement with that obtained by universal uniaxial tensile test at uniform deformation.

It has been well recognized that the load model has great effects on the power system analysis and control. For the convenience in practicality, it is necessary to build the load model parameter database for the large grid. However, there are large differences between the build of load model database and other power system components because of its special characteristics. In this paper, the building and revising strategy of the load parameter database is proposed based on the researches of field data selection, load classification, model synthesis and load model extension which also provides the guides for the application of the measurement-based load model in large grid.

This paper presents the fabrication of a novel micro-machined cytometric device, and the experimental investigations for its 3D hydrodynamic focusing performance. The proposed device is simple in structure, with the uniqueness that the depth of its microchannels is non-uniform. Using the SU-8 soft lithography containing two exposures, as well as micro-molding techniques, the PDMS device is successfully fabricated. Two kinds of experiments, i.e., the red ink fluidity observation experiments and the fluorescent optical experiments, are then performed for the device prototypes with different step heights, or channel depth differences, to explore the influence laws of the feature parameter on the devices hydrodynamic focusing behaviors. The experimental results show that the introducing of the steps can efficiently enhance the vertical focusing performance of the device. At appropriate geometry and operating conditions, good 3D hydrodynamic focusing can be obtained.

The change and development of the idea and culture of higher education in our country put forward new requirements for the campus planning and construction in institutions of higher learning. In this paper, the author discusses about the campus landscape planning through studying the traditional Chinese landscape architecture, so as to build campuses that are beautiful, comfortable, harmonious and poetic.

With the rapid development of high-speed railway, the problem caused by railway has become the focus of public attention. Whether the railway will damage the electromagnetic environment become an unavoidable topic. Choosing the AC 25KV high-speed railway to study, the impact of its resistive coupling on the human body or different devices is explored. Using the existing analytical formula, the ground potential rise caused by the resistive coupling has been simulated, which intuitively show the different ground potential rise in different situations. Finally, the impact of resistive coupling has been analyzed.

The application of Sea sand concrete, to solve the problem of affecting the durability become focus. Chlorine salt is sea sand concrete part. Based on cement, fly ash, sand, the desalination sea sand as experimental material. In were magnified 100 times, 1000 times and 8000 times of HCA0 (blending 0.01% chlorine ion without fly ash concrete), HCB0 (blending 0.03% chlorine ion), HCC0 (blending 0.06% chlorine ion) and HCD0 (blending 0. 1% chlorine ion) 28 days instar glue sand internal scanned , Using XRD analysis method, the chlorine salt to sea sand concrete microscopic morphology compactness was studied. The results of the study show that the microscopic morphology observation, chlorine salt to sea sand concrete compactness impact is not big, but chlorine salt can improve the compactness of concrete.

Coal transport security is one of the important links of mining safety in production chain. Most of Mines use long distance wire rope core belt conveyor transporting coal. By the reason of the load increases, the belt surface scratches and aging etc when the transmission belt in the long run, will cause the wire rope core corrosion, fracture, joint elongation, wire rope core and transmission belt adhesion decreased and finally the joint tensile fault. Once a fault occurs, the transmission security not only endangers mine, even causes the entire production system halted, so the security warning mechanism of coal transport tape proposed must be enforced. Article using machine vision and online transmission detection combined. In the first field observation, using the high accuracy linear array CCD real-time transmission of high-speed operation with the image acquisition and image processing threshold; Though extraction algorithm, simulation experiment and field test; finally comprehensive analysis gives the early warning scheme. The project mainly studies the transmission belt blob spot detection and algorithm with wear, based on digital image, image coding and image enhancement, compared the collected image speckle with set threshold so as to determine which set of real-time image for pre-alarm wear spots, mark the spot coordinates, at the same time to upload data in order to complete the transmission belt warning. The project solves the influence of transmission tape failure of coal production effectively.

Track association is an important role in torpedo anti- acoustic countermeasure. This paper put the multi-hypothesis targets algorithm which based on kalman filter theory into application of multi- targets track association. Data simulation experiment proved it that multi-hypothesis targets algorithm can effectively solve the measurement target data association problem .The target track can also be affirmed in short time

A design method of graph generator of laser shake mirror based on C8051F020 microprocessor is put forward and introduces hardware structure and circuit scheme. Through the modularized design method of software, kinds of graph can be outputed. Through test, this system can achieve its functions.

State estimation of power system is the basis of all the high level application and analysis for dispatch centers. Against the bad convergence of the WLAV (weighted least absolute value)-based state estimation method, a new robust state estimation method based on exponential weight function (E-LAV) is presented in the paper. This method uses an exponential weight function to replace discontinues weight function of WLAV to improve the poor convergence. The results of the sample system of 4-node system and the IEEE 118-node system show that the E-LAV-based state estimation method not only owns the similar convergence as WLS-based method, and also owns a strong robustness. Through modifying the weight matrix of the least squares, the proposed new method has good prospects for application in practical engineering.

Many researchers have studied the dynamics of the single-link flexible manipulator. A finite element approach is used in this study to describe the dynamics of the flexible link. The displacement of any point on the link is described in terms of modal displacements. Energy approach is used to formulate the equations of motion.

This article summarized seismic design method of high-rise building from seismic fortification goal, use of materials, structural systems, analysis methods and trends. Then it discussed the structural design significance of high-rise buildings to achieve sustainable development. Lightweight quality, high strength material, diversity type, spatial component, braced lateral force resisting system, structuring combination and shock absorption building are the trends of high-rise building development.

A dynamic comprehensive evaluation method of power quality based on incentive and punishment mechanism is proposed. At the beginning, the index system is designed and unified. Next, the incentive and punishment mechanism model of each index is established. Then, the vertical and horizontal scatter degree method and minimal variability theory are applied to calculate the comprehensive evaluation value of all the indices on every time period and on the whole time series respectively. Finally, the realistic example demonstrates that this method can easily differentiate the quality of different evaluation objects.

Melt flow and casting solidification are essential parts of the permanent mold casting process and affect significantly the quality of castings．For this reason, accurate prediction of mold filling pattern and temperature field in permanent mold castings plays on an important role in producing sound castings. In this paper, the model filling and solidification of a box casting produced from an aluminum alloy is studied. Different casting processes are employed, simulated and optimized to obtain sound castings. Simulation results reveal that with appropriate gating system, pouring rate, cooling line, a smooth mold filling, reduced shrinkages and other defects are available and desired sound castings can be produced.

In order to effectively inhibit the influence of constant bias of inertial sensors on strapdown inertial navigation system accuracy, a self-compensation method based on single-axis rotation modulation is proposed. It is shown by theoretical analysis that, the gyro constant drift and zero errors of accelerometer perpendicular to the rotation axis can be modulated to sinusoidal signal, which will be eliminated by integral. The constant bias along the rotation axis cannot be modulated. The effectiveness of the rotation scheme is proved by experiment and the influence of rotation speed is demonstrated.

The Thermal Decomposition Kinetics of Mg(OH)2 Modified with Sodium Dodecyl Benzene Sulfonate (SDBS) by the Liquid Phase Method Was Investigated Using Differential Thermal Analysis and Thermo Gravimetric (DTA-TG) at Different Heating Rates. the Results Show that the Mg(OH)2Modified with SDBS Is Mg(OH)2with Hexagonal Phase Structure. the Average Apparent Activation Energy of the Decomposition Stages of Mg(OH)2Modified with SDBS Was Calculated Using the Doyle-Ozawa and Kissinger Methods as 169.13 Kj•mol-1. the Reaction Order and Frequency Factor Can Be Also Determined by Kissinger Method. the Kinetics Equations of Reaction Were Deduced as Dα/dt = (5.71×1012/β) e-20340/T(1-α)1.52.

This paper researched on multi-period dynamic virtual cell formation problem, and filled the gap on objectives of previous literatures. A developed 0-1 non-linear mixed-integer mathematical model was proposed, it incorporates real-life parameters like alternative routings, operation sequence, duplicate machine, processing time and machine capacity. The advantage of the model is to embed the function relationship between cell size and internal production cost in the model, thus the effects of set-up cost, work-in-process inventory cost, coordination cost and inventory handling cost on VCMS are acted on the model. Finally a numerical example solved by Lingo11.0 software package was presented to verify the model and related discussion was made. The results show that the cell size changes as time in dynamic condition and different scenarios of internal production cost can obtain different cell configurations.

The present study is related to a process development for producing high purity fused magnesia. A newly designed 3000 kVA electric arc furnace is used in the field experiment. The electric resistance characteristic of fused magnesia is analyzed and the effect of electrode diameters and electrode depth buried in molten magnesia on melting electric resistance and electric arc heat conversion are discussed in detail. It shows that, for the new 3000 kVA electric arc furnace, 350~450 mm diameter electrode and ~300mm depth in molten magnesia are suitable.

This paper presents a fault diagnosis method for nonlinear analog circuit based on multifractal detrended fluctuation analysis (MFDFA) method. The MFDFA method is applied to analysis fault signal and extracts the multifractal features from the raw signal. The selected features are given to SVM classifier for further classification. The data required to develop the classifier are generated by simulating various faults using Pspice software. The simulation results show that the proposed method provides a robust and accurate method for nonlinear circuit fault diagnosis.

Lake eutrophication and algal bloom is one of the most important environmental problems facing China's lakes, and it is also the focus of lake eutrophication control of the world's attention. The monitoring data on chlorophyll concentration was analyzed every one month, combined with corresponding weather conditions from 2004 to 2006. According to the degree of eutrophication in Taihu Lake, it is divided into five Lakes: heavy eutrophication region V, eutrophication region IV, middle-level eutrophication region III, light eutrophication region II and nutrition region I. Based on fuzzy factor optimization method, the average wind speed, average pressure, average temperature and sunshine hours was selected to discuss the influence mechanism of meteorological factors on the algae bloom in Taihu Lake. Considered the four meteorological factors as the input layer nodes, BP neural network model was applied to build the zoning monitoring and early warning model of blue algae in Taihu Lake.

The mechanical properties and microstructure of the high strength low alloy HC340LA were obtained with different strain rate. The research shows that the better plasticity, higher tensile strength and yield ratio can be found in high speed tensile state than in quasi-static tension. The plasticity and tensile strength decrease with the increasing of the strain rate during the high speed tension. With the increasing of the strain rate, the grain size of the ferrite decreases and its distribution is uneven, and the grain boundaries increases. The HSLA steel HC340LA submit to obvious Ductile Frecture mechanism. The size of the dimples is more uniform, bigger and deeper with the strain rate 50 s-1 than with the strain rate 200 s-1. Therefore, the higher strain rate with over strain rate 50 s-1 has less Superscript textcontribution to the improvement of plasticity of the HSLA steel HC340LA.

An improved Shear Stress Transport(SST) model, which allows for the compressible corrections, is proposed in this study. Numerical scheme was established by taking advantage of the improved Total Variation Diminishing (TVD) scheme and by applying implicit scheme to the negative source terms of the turbulence model. Hypersonic flat-plate boundary-layer flows and hypersonic compression ramp flows marked with separation, reattachment and shock/boundary-layer interactions are then computed. The comparisons between the computational results, the experimental results and the semi-empirical formulations show that the compressible correction term of the SST turbulence model is the scalar product of the weighted density average of the turbulent fluctuating velocity and the pressure gradients of the average flow field correlation quantities. In addition, for flow with separation and without separation, calculation results of wall pressures, friction coefficients and wall heat transfer rate distributions using the improved model and established scheme agree better with the experimental results than that using the original SST model.

The flow field characteristics in U-typed bend has been extensively studied for transit time ultrasonic flowmeters designing, but for the flowmeter with three-Z-shaped round pipe there is still lack of corresponding research. This paper presents a computational fluid dynamics (CFD) approach for modeling of the three-Z-shaped ultrasonic flowmeter and studying of internal fluid field characteristics based on Reynolds stress model (RSM). The fluid velocity profile in the three ultrasound path is obtained using CFD and secondary flow in cross section also is analyzed. The simulation results show that the internal flow fields in the flowmeter are not fully developed turbulence with asymmetric axial velocity distribution and dramatic changes along the flow direction, and there are obvious secondary cross flows on theirs cross-sections. The CFD simulations provide useful insights into the flow field associated with ultrasonic flowmeters design.

This paper states the definition of evolutionary dynamic of project organization, finds out the dynamic factors of evolution of the project organization basing on talks, questionnaires and analysis, constructs the diagram of dynamic factors, basing on which a three-dimension graph of the interaction between dynamic factors is constructed, and a model about the interaction process between dynamic factors basing on Haken Model is built and a analysis about the process is made. The author concludes it’s an effective way to make the organization change from criticality to orderly state faster and the evolution of the organization by means of designing dynamic factors rationally, dynamic construction of the relationship of competition and cooperation and enhancing the rational actions the behavior subjects.

This paper attempts to explore design methods of residential areas that reflect regional construction from the planning, architectural design, and landscape and through extraction and analysis of influential elements of regional areas. The study aims at providing certain theoretical guidance for construction of regional areas and giving inspiration to creation of regional residential areas based on better inheritance of historical context and natural environment in the region to achieve people’s desires of a more comfortable, safer, and more sustainable living environment.

To monitor aircraft flight status, predict the position of aircraft is needed. By the research of the kalman filter, particle filter, and the best curve fitting method, use the last before time or several before moments‘s flight state data to predict the state of the aircraft, even forward time’s state, the dynamically weighted average of the multi-times data can get to the aircraft status data and subsequent flight status data, so the aircraft fly normally and smoothly with the predicted status data, that can get a good visual effect. The algorithm experiment is through the extraction data from the real aircraft data, the average relative error is 0.03%.

In the rapid development process of cylindrical drip emitter, the traditional CFD analyzing method was generally carried out based on the planar model of the cylindrical labyrinth channel. However, the result obtained by this method was obviously different with the experimental data. In this paper the cylindrical prototype of the labyrinth channel was proposed and the CFD analysis was carried out based on the hexahedral mesh of the cylindrical labyrinth channel to solve this problem. Then the flow rate and the anti-clogging performance of the emitter were predicted based on the stereo prototype of the labyrinth channel. Consequently, the simulation results were verified and the cylindrical drip emitter was finalized according to its hydraulic performance experiment.

Following the modified Gurson model in meso-mechanics, the models with spherical holes are established by the assumption which the matrix meets the two-parameter elliptic yield condition. The macroscopic stress expression which contains micro structure parameters and the material equation of yield surface are given by the upper bound theorem of plastic limit analysis. The parameters of the matrix material and damage(porosity) which impact on macroscopic yield surface equation are discussed. These works provide theory foundations for material damage and design.

For making the conceptual design process optimization, achieve its various function demand, and confirm the optimal proposal. Contra pose the shortage of conceptual design process, combine the basic national conditions in china, we put forward the basic definition of the conceptual design. Firstly we discussed the basic content and basic step of the conceptual design, secondly, we analyzed demand design, function design, principle design and conceptual design according to designing weapon cupboard for the armed forces department in swallow village located in Hefeng country. We get the superiority of the conceptual design, Benefit designers to use their talents, benefit the innovative design, Stimulate the product design standardization and formulation, benefit product design sustainable and rapid development.

In order to solve problems and modify design deficiencies in safety testing of baby carriages, a new collision and impact test machine is designed. Force and movement are analyzed by physical modeling of the test machine. The use of virtual prototyping technology to simplify the testing machine model and velocity, acceleration parameters and energy loss diagrams of measured object are obtained by dynamic simulation of the test machine model. The analysis results are obtained by comparative simulation of group data which show error of the test machine on collision velocity and impact energy fully meet the requirements of domestic and international testing standards and much lower than error of traditional experimental methods. The experimental method is verified feasibility and advanced in theory and provides a theoretical basis for developing the test machine.

The geological structure is very complex in Haita Basin, due to the difficult drilling, sidewall instability phenomena happened frequently during drilling process. And it has restricted the drilling speed and the development and exploration process seriously. According to the borehole collapse problems, physical and chemical properties experiment of mud shale had been operated, then we analyzed and predicted borehole stability of Haita Basin by experimental data, discussed the collapse mechanism in this area, and established corresponding countermeasures to prevent the collapse which has laid a good foundation for further research on key drilling technology and improving drilling rate in Haita Basin.

In order to solve the traffic jams and congestion of urban transportation in most cities, the steel trussed cable-stayed car overpass model is analyzed through the finite element modal analysis by ANSYS software based on the design concept of straight going fast assembling car overpass. After understanding the laws of free vibration characteristics of the structure, the variation of maximum deflections and stresses of the structure which is under the loads moved at different speeds are studied by moving load transient analysis of full method. The result further testifies that the structure is reliable and safe. Also, the range of the optimum speed is summarized to provide reference for the design of speed-limiting facilities of the car overpass.

the set pair analysis method that deal with uncertain problem of system and Markov chain theory that research the transition law of system state was appled to establish the dynamic assessment model for safety management of bridge construction. Taking a bridge construction project as an example, this paper conduct a dynamic assessment through five time intervals and come to a conclusion that the assessment results are general and they need rectification, but the system state is developing into a favourable level. And the evaluate results verify the rationality of the model.

For hypersonic compressible turbulence, the correlations with respect to the density fluctuation must not be neglected. A Reynolds averaged K-ε model is proposed in the present paper to include these correlations, together with the Reynolds averaged Navier-Stokes equations to describe the mean flowfield. The K-equation is obtained from Reynolds averaged single-point second moment equations which are deduced from the instantaneous compressible Navier-Stokes equations. Under certain hypotheses and scales estimation of the compressible terms, the K-equation is simplified. The correlation terms of the fluctuation field appearing in the resulting K-equation, together with a conventional form of the ε-equation, are thus correlated with the variables in the average field. The new modeling coefficients of closure terms are optimized by computing the hypersonic turbulent flat-plate measured by Coleman and Stollery [J. Fliud Mech., Vol. 56 (1972), p. 741]. The proposed model is then applied to simulate hypersonic turbulent flows over a wedge compression corner angle of 34 degree. The predicting results compare favorably with the experimental results. Also, comparisons are made with other turbulence models. Additionally, an entropy modification function of Harten-Yee’s TVD scheme is introduced to reduce artificial diffusion near boundary layers and provide the required artificial diffusion to capture the shockwaves simultaneously.

This paper presents a procedure of calculating cogging torque of Permanent Magnet Synchronous Motor (PMSM) for NC machine tool servo-system based on finite element method (FEM). Simulation models of PMSM are established to complete coupled calculation between magnetic fields and mechanical dynamics. Furthermore, the distributions of magnetic flux and electromagnetic force densities are also gained. Finally, the cogging torque of the motor in operating process is suppressed by changing slot opening configuration. The references for the optimization design on NC machine tool servo-system are provided by the simulation model.