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To overcame the shortcoming that the CBTC interoperable system cannot deal with temporary speed limit informaiton across ZC control zone, a new interoperable DSU structure incorporated into the existing CBTC is studied and designed. Interface between subsystems and Data Storage Unit (DSU) systems changes are illustrated and analyzed, and also the interactions between subsystems are given. Based on characteristics of interoperation CBTC system, a novel DSU system architecture is designed, its modules are divided into the temporary speed restriction module, line database module and system maintenance module. Performance test of DSU system is conducted in the interoperation test platform in Chongqing. The results show that DSU system can meet the requirement that trains can cross the line and improve the efficiency of interoperable operation.

The total focusing method (TFM) attracts much interest because of high image resolution and large dynamic range. However, the signal-to-noise ratio (SNR) of TFM is relatively low due to single-element emission. Especially in highly attenuating materials, the signal amplitude may be reduced with depth to a level lower than the electronic noise introduced by the signal acquisition system. Golay-coded excitation was introduced to overcome this problem, however, the double-excitations reduce the time resolution and may lead to negative decoding performance due to the relative change of scanning positions. In this work, the AB code conversion factor was used to realize the TFM imaging based on Golay-coded single-excitation which has a good performance as traditional Golay-coded excitation. A series of simulations and experiments were conducted to compare performance of TFM using un-coded excitation, Golay-coded excitation and modified Golay-coded excitation. TFM using modified Golay-coded excitation could overcome the disadvantages of double-excitation, and has approximately the same SNR gain as TFM using traditional one.

The condition of urban tourism development, including the urban tourism resources, accessibility, visitor perceptions, cognitions, market segmentation, market demand and market competitors are analyzed. Then based on the current status of the development of urban tourism, the urban tourism product development and makes systematic study of each category is classified so as to arrive at the general idea of urban tourism product development. Qingdao urban tourism product development is selected as an example to analyze the condition of Qingdao urban tourism product development, and based on the current status and questions of Qingdao urban tourism product development, the enhancement suggestions of its development is proposed to improve the research system.

Thermal hydraulic performance analysis of fuel rod bundle with spacer grids takes important role among the pressure water reactor (PWR) design and safety operation. Due to its intrinsic complex geometric configuration, previous studies were almost based on one-dimensional code and many simplifications had to be made to make simulations manageable. In the present paper, the intact and simplified spacer grids were simulated and analyzed by using the Computational Fluid Dynamic (CFD) software, and efforts were emphasized on the influence factors on the flow field including spacer grids with mixing vanes only and spacer grids with mixing vanes springs and dimples, respectively. The results indicate that the springs and dimples have great influences on the flow field and thus cannot be neglected during numerical simulation of coolant flow through subchannels with spacer grids. The transverse flows and pressure drop with springs and dimples show more intense than those without spacer and dimples as expected.

AIS (automatic identification system), a new type of the radio navigation system at sea, can provide more target information than radar. It is very important how to make a desk officer intuitively observe the information so as to conveniently judge the motion tendency of the targets around own ship. We had developed a system of the AIS information display based on the platform of ENC (electronic nautical chart) by using Microsoft VC++ software tool. The 6 bit encapsulated data from the AIS output interface were received and decoded. After being converted into ASCII code in the format, the AIS information was showed on the platform of ENC with both graphic and alphanumeric mode, complied with the international criterion. The results of a spot test show that the system has a lot of advantages including good interface and so on.