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A new evaluation index system, which includes five dimensions is put forward to evaluate the competitiveness of construction subcontracting enterprise properly. Based on GA optimized BP neural network model,construction subcontracting enterprises’ competitiveness can be quantitative analysis systematically. Use of Matlab simulation analysis,research has shown that this system can well solve the problem of construction subcontracting enterprise competitiveness evaluation.

In order to optimize the structure of steel tube arched bridge, the parameterized model of steel tube arched bridge shall be established on the basis of APDL of ANSYS finite element. based on the huge computational power of ANSYS and the flexibility of APDL parameterization language, choose width of longitudinal beam, radius of arch ring and radius of suspender as design variables, regard maximum deflection and maximum stress as state variables, and take total volume as objective function. Realize structure optimization analysis of steel tubular arched bridge via parameterization computation.

The principles and method of computational fluid dynamics were applied to numerical simulate the external flow field about the SUV model. The hybrid mesh of tetrahedral and triangular prismatic as well as the turbulence model of Realizable k-ε was adopted to study the flow field of SUV of flat underground. Then the SUV of complex underground was simulated with the same mesh strategy and boundary condition. The aerodynamic drag coefficient of latter was bigger than former. That illuminated the complex underground has affect to aerodynamic performance of vehicle. The wind tunnel test validated the veracity of numerical simulation. Based on that, the underground cover board was appended; the aerodynamic drag coefficient was depressed. The velocity and pressure distribution and flow line were achieved. The conclusions provide theoretical reference for the further study of aerodynamic drag reduction of complex underground.

In order to respond to the energy crisis and environment problem, countries carry out their research and promotion about electric vehicles. As the ten cities one thousand new energy buses started in 2009, the new energy vehicles have been greatly developed in China, while the development of electric vehicles is not that good. This paper selects four cities-Los Angeles, Kanagawa, Hamburg, Amsterdam-that promote electric vehicles successfully and deeply analyzes the development of electric vehicles in these four cities and analyzes the factors that affect the development of electric vehicles in three aspects-city environment, government and stakeholders. Then the paper discusses the promotion ways and role of government and consumer. Finally, the paper offers some suggestions to promote electric vehicles in China: focusing on feasibility and adaptability of electric vehicles, playing government`s leading role, improving low-awareness and acceptance of electric vehicles and focusing on user requirements.

Based on moving grid and dynamic boundary conditions, the transient aerodynamic characteristics of the flow field around vehicle were studied when simplified model was driving in the crooked road. The influence of curvature radius on aerodynamic characteristics was studied through the analysis of the drag coefficient, the side drag coefficient and the changes of the flow field. The conclusions provide theoretical reference for the further study of the transient aerodynamic characteristics of turning vehicle.

This paper focuses on a new method of aerodynamic drag reduction. In this paper numerical simulation method is adopted to investigate the relationship between the aerodynamic drag characteristics of a blunt body and the distribution of total pressure around the body. The study shows that when the shape of a blunt body is modified to be close to its isobaric surface, the pressure drag of the body can be reduced largely while the viscous drag increases slightly, and the summary of the drag gets lower as a result. This conclusion will have profound guiding significance in the aerodynamic shape designing and the aerodynamic drag reduction of an automobile.

The aerodynamics characteristics of square Mira model were researched by simulation, the drag coefficient and the aerodynamic characteristics around model were achieved with analysis of velocity and pressure distribution. Based on results, the angle of rear wind window, the angle of underbody diffuser and the front transition radius were changed, the drag and lift coefficients were achieved. The conclusions provide reference for how to reduce drag coefficient of SUV

At present, NASA is engaged in research to develop Plasma flow control technology on aeronautic and astronautic scopes. This article presents a compositive MHD(magnetohydrodynamics) method to control high-velocity Plasma flow generate by alkali salts in combustion gas, demonstrates that MHD system can make the jet plume to deflect, and realizes the aeroengine thrust-vector purpose. By analyzing and applying the MHD mathematical model, the author performs the numerical simulation of plasma flows-field with the MHD condition，shows that the jet plume in plasma state can deflect with MHD.

Based on overlapping grid, two cars were simulated numerically through computer when lane-changed overtaking and the aerodynamic characteristics of two cars were achieved. By analysis the coefficients of side force and yawing moment and the flow field around two cars when two cars’ position changed the flow motivation and rules of interference each other were researched. The conclusions can provide the theoretical foundation for the research of transient overtaking

Based on overlapping grid, two cars were simulated when lane-changed overtaking and the aerodynamic characteristics of two cars were achieved. By analysis the coefficients of side force and yawing moment and flow field around two cars when two cars’ position changed the flow motivation and rules of interference each other were researched. The conclusions can provide the theoretical foundation for the research of transient overtaking.

Research was done on the crosswind aerodynamic loads of three different front shape heavy-duty trucks by the method of numerical simulation. According to the research, the side force and the rolling moment of truck change slightly, but the drag and yawing moment changes dramatically when running in strong crosswind with different front shapes. The conclusions were drawn from discussion that the long head heavy-duty truck has the least yawing moment among the studied trucks so it has the best driving stability correspondingly.

The two turbulence models were used to numerically simulate the external flow field around the Ahmed standard car model, and the aerodynamic drag and lift coefficients and aerodynamic characteristics around model were obtained. By comparison between the simulation results and the corresponding wind tunnel test data, the differences of two turbulence models were analyzed. The results indicated the simulation result of RNG k-εturbulence model is more precision, and it is more suitable on numerical simulation in vehicle external flow field. The conclusions provide reference for how to select turbulence model.

Association rules can mine the relevant evidence of computer crime from the mass of data and association rules among data items, and further mine crime laws, trends and connections among different crimes. It provides police’s case detection and crime prevention with clues and criterions. This paper firstly analyzes the application of FP-Growth algorithms in computer crime forensics, points out the defect of FP-Growth algorithms that can’t timely find the latest crime and the serious crime, and then puts some improvements of the FP-Growth algorithms and tests it by carrying out experiments. Finally, it points out the future research aspect: extraction and correlation of multidimensional evidence.

Based on the theory of infrared absorption, a new kind of portable methane alarming device has been developed with the advantages that cost-low, maintenance-free, miniaturization, and integration. Intrinsically safe circuit is absolutely necessary, because the device is installed in the explosive gas environment. To improve the detection accuracy and increase the safety of the coal mine, the device’s intrinsically safe circuit has been designed. All parameters of the circuit are designed in accordance with IEC 60079-0-2007 Explosive atmospheres-Part 0: Equipment - General requirements and IEC 60079-11-2006 Explosive atmospheres-Part 11: Equipment protection by intrinsic safety “i”. The related analyses and calculation results show that this intrinsically safe circuit is workable and reliable.

1,4-butylene bi-p-hydroxybenzoate (BBHB) was synthesized using methyl p-hydroxyl- benzoate and 1,4-butanediol under catalyst and stabilizer conditions; Then, the thermotropic main- chain liquid crystalline polysiloxanes (MCLCPs) with flexible spacer, were synthesized using BBHB and dimethyldiethoxysilane reagents by melting polycondensation. The chemical structures and properties were characterized by FT-IR, polarized optical microscopy (POM) and differential scanning calorimeter (DSC) respectively. It was found that MCLCPs was the type of smectic A liquid crystal, and the liquid crystal temperature ranged from 58°C to 143°C, i.e. its variationrange reached 85°C. In addition, the polysiloxane was used as the flexible main-chain and the flexible chains CH2 was embedded into the rigid structural blocks of liquid crystalline polymers, which not only decreased the melting point below the thermal decomposition temperature, but also made the clearing point and a stable liquid crystal state observed.

Study the issue of hospital information performance, improve hospital information management efficiency. For the issue of hospital information system disk competition, high-speed buffers and low hit rate shared pool, resulting in the problem of long time user waiting, low efficient system support for system throughput, optimization improvement for hospital information systems. First, to optimize the architecture of the database, and then rationally design system global area, disk I / O and connection pool etc in the memory area, finally reasonably organize the SQL statement. Apply to the optimized hospital information system into the Medical, example shows that optimized hospital information system improved system throughput, reduced the user waiting time, and greatly improved the operation efficiency of Medical College.

To research the aerodynamic characteristics of minibus, the simplified model is studied with simulation and wind tunnel test. The validated method was adopted in the numerical simulation, the wind tunnel test were carried out in order to validate the results of numerical simulation. The tests include aerodynamic drag measure, filament method, and laser flow visualization. Through the contrasted research the results of simulation and test, the aerodynamic characteristics of minibus was analyzed and the characteristic of field around minibus was discovered. The conclusions provide the theoretical foundation for styling optimization of minibus, which are very helpful to develop new vehicle styling.

Integral inference method for multi-state type-Ⅱcensored data is presented, which is used to evaluate the rupture life of composite material. The best unbiased estimators for the model parameters, the standard deviation and their covariance are also given. The confidence limits of the acceleration equation and the confidence intervals of percentiles for Weibull distribution are discussed in detail. According to the presented method, the experimental information of accelerated rupture life is fully exploited, and the cross information among test data in different stresses are analyzed as an integration.So its information quantity is much bigger than traditional group test method. The method provides a feasible and effective approach to rupture life evaluation and reliability estimation of composite material.

Emergency management theory based on existing research results is studied, and a flexible solution of emergency management information system is proposed. It is divided into five layers: data storage layer, business logic layer, presentation layer, integration web service layer and integration communication interface layer, mainly involving computer software, network communication, information system development and other technologies. The solution proposed will be benefit for developing and achieving the flexibility and integration of emergency management information.

The shell model (SM) can simulate dipole and other properties concerning electrons. In this paper, an new scheme of SM potential is developed. Unlike the traditional SM, there are no harmonic spring between core and shell, and the potential functions are Coulomb potential multiplied by trigonometric function. The parameters of SM for hydrogen system were fitted by electronic structure data, which is from quantum chemistry ab initio calculation of H, + 2 H and 2 H . And the potential was examined by calculating the most stable structure of H2 and + 2 H by geometry optimization globally, which is agree with the ab initio calculation results. Furthermore, even the energy level of H atom can be calculated by this scheme SM potential, but the reasonable results can not obtained.

According to actual of cow epidemic disease diagnosis, bidirectional reasoning scheme based on the symptom both characterization and autopsy is proposed, which is based on inexact reasoning of certainty factor. The process of both construction the knowledge database for cow epidemic disease diagnosis and the inexact reasoning based on certainty factor are amplified. A web-based system on the platform of Tomcat+JSP+MySQL+DWR about the cow epidemic disease diagnosis is realized base on MVC. By testing, it is shown that the monitoring 21 kinds of cow epidemic disease in China can be accurately diagnosed, basically. It can be widely used in breeding aquatics village, breeding farm, raising households and so on. It will play a positive role to prevent and control the cow epidemic disease.