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Exploiting the structural merit that electric motors can be controlled precisely in speed und torque, this paper investigates the use of Torque Vectoring Control (TVC) for improving handling of electric vehicles. The strategy consists of two control levels. The upper level controller layer achieves reference yaw rate tracking, by using the 2-DOF planar bicycle model with a linear tire model to calculate the desired yaw rate. Then with sliding mode control law the desired yaw moment is determined. The lower control level determines control inputs for four driving motors by means of optimum traction distribution. Simulations are carried out by using the co-simulation of vehicle dynamics software CarSim and Simulink to verify the effectiveness of this control system and the effects of parameter variations (friction coefficient and throttle).

Automated assessment technology for subjective tests is one of the key techniques of exam systems. A model based on domain ontology is proposed in this paper, which can be used in exam systems to estimate subjective tests. After analysing the present research status of subjective automated assessment technology, the paper makes a study on the construction method of domain ontology by taking software engeering domain as an example. Semantic similarity calculation based on domain ontology is used for automatic assessment in this paper. The automatic assessment system can divide a sentence into a series of phrases by using the natural language processing technology and get the score by evaluating the semantic similarity of the student's answer. The experiments show that the results of the system which has certain valuable feasibility and applicability are credible and the scoring errors are acceptable.

The torque vibration derived from in-wheel-motor transmitted to body frame through suspension system without the absorption of mechanical transmission parts, then excited every body panel to shape the vehicle interior noise, which influenced the quality of the vehicle NVH. This paper aims to build an accurate suspension system simulation model to analyze the influence of suspension parts parameters to system vibration transmission property. Basis on a novel empirical model of rubber bushing, a multi-rigid suspension model and a multi-flexible suspension model had been established respectively. The vibration characteristics of two models were simulated, furthermore the swept-sine exciting vertical force signal on wheel contact point were input on the simulation models to find the difference between rigid and flexible model. The simulation results show that: the multi-flexible model can reflect the vibration characteristics of the suspension system more accurately in the high frequency range and so is it more applicable to the simulation analysis of vibration characteristics of in-wheel-motor electric vehicle suspension system.

The evaluation index of execution control system of freeway construction project is established in this paper. And Delphi method is adapted to analyze the weights of index system. Then the extension comprehensive assessment method is adapted to analyze the execution control system performance of a key freeway construction project, and the corresponding suggestions and countermeasures are given. The goal of this kind of performance evaluation method is clear, and the maneuverability is strong. It has good stimulative effect for the real-time execution, control and adjustment of freeway construction project.

In this article, the preparation and application of solid neutralizing agent was studied, liquid acid to purify crude biodiesel traditionally was substituted for the solid neutralizing agent and acquired satisfactory results. It was the biggest advantage to the process to apply solid neutralizing agent to purify crude biodiesel that became more simple than former and may not produce wastewater, the drawback of production biodiesel at present can be successful improved.

Under the influence of development in digital science, a trend of digital design is growing quickly in the contemporary architecture. According to the function for design process, digital design technology of contemporary architecture can be summarized in three aspects: representation technology, generative technology and supporting technology. In this paper, it will study on the main idea and content of each technology, in order to discover the new developing direction of digital architecture design methods

Procedural modeling is one of the widespread uses in the field of computer graphics technology, even in urban design. According to the object of urban design, procedural modeling technology can be summarized in several methods: procedural modeling of cities, interactive procedural street modeling, automatically generating large urban environments based on the footprint data of buildings, cellular automata and software agents, shape grammars. In this paper, it will study on the main idea and content of each technology, in order to discover the new developing direction of procedural modeling design methods in the field of urban design.

Wheel hub bearings are weak parts in wheel driving system because of its bad condition of loads. This paper has selected two typical extreme working conditions for vehicle, namely braking with turning and driving with turning, and analyzed loads of wheel hub bearings. The design parameters of wheel hub bearings are analyzed separately, with the purpose of finding the key parameters in them, which influenced the force of bearing, and finally these important parameters for structural design have been optimized, the force of wheel hub bearings has been decreased by 45%.

Procedural modeling is a term in computer graphics referring to the creation of digital models with sets of rules. With the user-defined rule sets, digital models can be generated automatically by computers rather than modeled manually. Several popular procedural modeling methods and are listed and compared in the paper. A new research framework on procedural modeling of urban and architecture form is introduced. We also choose Jørn Utzon’s “additive architecture” as a case study and show the possibilities of future urban and architecture design.

This paper puts forward one new anti-skidding method based on the model following control method. With the new feedback function and control parameter, the braking performace, especially the phase-delay of the electric motor's torque is, according to the result of the simulation, improved. Combined with the advantage of the origin MFC, we think the improved MFC can be widely applied in anti-skidding method.

In this work, silicone/alumina composites with 33 wt.% silicone content are prepared by compression mould technique. TGA, XRD and SEM were used to characterize the ceramifying behavior when the samples were heated from 600 to 1600°C. XRD results suggest that the ceramic residue of SR could restrain the phase transformation of γ-Al2O3 below 1100°C, indicating that the chemical bonds preserve the mechanism strength of SR/Al2O3 composites under high temperature. The flexural strength increases from 18.19 MPa to 75.31 MPa with the increasing temperature from 600 to 1600°C, owing to the sintering reaction between SiO2 and Al2O3 forming mullite phase under higher temperature. It has low liner shrinkage after firing and nearly no macrocracks or deformation under any temperature, illustrating that the SR/Al2O3 composites can be used as organic fire-retardancy materials.

SR/Al2O3 composites were fabricated from different heat treatment temperatures of alumina. The results show that the relative density is over 94% and flexural strength is 66.5MPa when silicone content is 33wt.%. The flexural strength of the obtained SR/Al2O3 composites is decreased when increasing the heat treatment temperature of sandy alumina, indicating that the surface hydroxyl groups directly influence the flexural strength of SR/Al2O3 composites.