Considered waste glass and scrap aluminum as raw materials, preparation of waste glass and scrap aluminum composite materials by using mechanical mixing method. Composite material properties were studied by experiments. With the increase of the glass particles, the composite tensile strength and hardness are improved, wear resistance is increased much more than the matrix, it provides useful help of the use of waste.

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A signal generator with adjustable frequency, phase and duty cycle is designed in this paper. The design of this signal generator is based on the technology of direct digital synthesis (DDS).The classic structure of DDS is presented and its principles are introduced in detail. The key modules of the design such as phase accumulator and pulse width processing are implemented by verilog HDL language. With suitable FPGA, the designed signal generator and all modules of the design are simulated successfully in Quartus II.

With the numerous applications of high-pressure pipeline, it is very important to simulate the in-service welding of the pipeline.The flow state of the medium in the pipeline can be analyzed, the temperature field and the stress field also can be simulated by applying sysweld software. The medium flow can reduce the welding residual stress and reduce welding stress range during in-service welding. Meanwhile, with the increase of flow rate of the medium, the maximum temperature of inner wall drops and the maximum weld residual stress increases by a slow growth. At the same time, the highest temperature of pipe wall increases rapidly with the increase of heat input, whereas the maximum residual stress of welded joint decreases by a slow trend.

In this paper, it was introduced that the case that under100% replacement of recycled coarse aggregate (RCA), the C30 recycled concrete was prepared by different rage fly ashes 0%, 10%, 20%, 30% replacing cement. The strength of the recycled concrete and mixtures workability were test. Eventually it is concluded that the strength and mixtures workability of recycled concrete were affected by different circumstance under the different rage and amount of fly ashes, and a theoretical basis in the impact of fly ashes in the application of recycled concrete is provided.