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With the complexity of system design growing, the high quality software design are needed. In this paper, the design procedures based Model-Based Design of line-of-sight control system using MATLAB/Simulink blockset and code generator tools for TMS320F2812 DSP is presented. This approach complete the control algorithm simulation and system architecture design using Simulink model, generates the executive code for DSP target with Real-time workshop and embedded coder. The effectiveness of this procedure from the analysis stage to real system implementation is experimentally verified.

Buton Rock Asphalt is a natural hard asphalt which is relatively rich in asphaltene and very low in wax. Through researches and practices, it is proved that the mixture of a certain amount of rock asphalt into the petroleum asphalt for regular roads can considerably improve the adhesivity of asphalt and aggregate and the high-temperature stability, low temperature crack resistance and water susceptibility. Relying on Guangdong Shantou To Jieyang Expressway, this paper applies Buton Rock Asphalt (hereinafter referred to as BRA) to making 70 Aiptek (hereinafter referred to as the IRPC-70) be modified, tests and analyzes the asphaltene content of the BRA and mineral levels and studies the influence of the BRA content on performance of modified asphalt. In the mixture design phase, it studies the impact of aggregate gradation after the BRA accession, obtaining the correction factor of the key sieve’s pass rate. Finally, the BRA mix design and pavement performance has been studied by the test section.

Through analyzing the real collision process of a steel plate rolling sliding off a lorry and box girder flange of an overpass, the damage degree of box girder may be known, and in this article the collision process is also simulated by means of finite element method so that it may be obtained how the damaged girder collapses and the cracks propagate. Furthermore, the dynamic characteristics are studied during the collision process and the reliability of overpass section collision is analyzed from the angle of energy transfer and dissipation.

According to the computing formula of the effective relative density of aggregate and its physical significance, the theoretical computing formula of asphalt absorption coefficient C has been deduced through the Four-phase system theory of aggregate, and the rationality of asphalt absorption coefficient has been verified through testing and comparison with other computing methods. It is concluded that: (1) the asphalt absorption coefficient is between 0.2 and 0.8 when the water absorptivity of aggregate is between 0.5% and 4.0%; (2) the formula of asphalt absorption coefficient should includes bulk relative density of aggregate; (3) when the water absorptivity of aggregate goes up, the impact exerted by the bulk relative density of aggregate upon the asphalt absorption coefficient would be greater accordingly.

The method of strain-based fatigue analysis is applied on the study of fatigue behavior of reinforced concrete (RC) beams strengthened with fiber reinforced polymer (FRP) laminates in this paper. Based on the investigation of fatigue performance of RC beams strengthened with FRP laminates presented in the published literatures, the values of stress concentration factors and the coefficients in Neuber’s rule are suggested. The exponent of fatigue strength in Manson-Coffin formula is discussed so as to having a general stain-life curve which is suitable for the fatigue behavior prediction of RC beam strengthened with FRP laminates. The S-N curves of different stress ratios can be developed and the fatigue lives of the strengthened beams are pointed out.

Density should impact sustainable transportation but its exact role is still under discussion due to various interpretations and inconsistencies in the literature. To explore its impact on urban recreational travel in large Chinese cities under rapid urbanization, this paper took Shanghai as a case, studied its spatial patterns of both population density and road density, surveyed 11 popular urban parks on user access modes and analyzed the mode changes in spatial terms. The passive effect of low-density urban sprawl on sustainable recreational travel in large Chinese cities was addressed.

The bridge is a half-through steel-pipe concrete arch bridge with uniform catenary. Based on sufficiently considering the principle of symmetrically loading rib concrete, the pouring process of the whole concrete is calculated with emulation with the aiding of commercial package MIDAS/Civil. By analyzing the structural deformation, stress and stability, the structural responses such as the structural distortion deformation, bearing-force characteristics and stability coefficients at different construction stages are computed in this study. The motivation of this investigation is to ensure the structural safety, and the structural security can also be discussed. The made observations indicate that the whole bridge has a high safety in either construction or operation and the achievement of research may provide reference for the similar arch bridge.

The cavity, formed at the nose part of underwater launched vehicle due to the high launching velocity, will collapse while crossing water free surface and has a great impact on the strength of vehicle structure. In order to study the effect of the cavity collapse to vehicle structure, water exit dynamic analysis has been conducted. Before that, the computational model has been established. The external load, caused by cavity collapse, is assumed to be concentrated pulse forces applied on the vehicle at different time. And the flight vehicle structure is simplified into a free-free Timoshenko beam. The Fluid Structure Interaction (FSI) effect is treated as added mass and hydrodynamic drag force varying with wet surface area, which decreases with the water exit of vehicle. The dynamic response, excited by the external load, is calculated. Result presents the necessary of taking account of FSI and the influence of time space between the two concentrated forces.