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Construction of the urban rail transport system in China is witnessing a fast-developing period. This industry needs a large number of special talents in the area of design, construction, equipment manufacturing and operation management. Over recent years, some Chinese universities have launched mass transit programs in response to the growing demand of the rail transport market. In this paper a study is made on the cultivation level and orientation of rail transit talents at China’s universities, with the existing problems analyzed, summarized and the solutions presented.

Buddy algorithm is one of the classical algorithms for Linux Memory Management. In buddy algorithm, free memory blocks, even if they have the same size and consecutive address, they cant be combined into a larger memory space because they dont have a partnership. For these shortcomings of the algorithm, this paper proposes an improved buddy algorithm which mainly include in the main data structure adding an array and a variable respectively to record the starting address and the number of two adjacent free memory blocks which are in the linked list of last order and do not meet the partnership, at the same time, improving memory allocation management and memory recovery management.By experiment, when the memory space is insufficient and memory allocation request is frequent, the improved algorithm can effectively reduce the number of failed memory requests and improve the memory utilization.

The conventional valves used in the choke manifold for well control usually have intensely nonlinear characteristic of the match between pressure choking and vale opening. Therefore, it is difficult to achieve the precise choking pressure that is essential to the managed pressure drilling (MPD) through a single throttle within the scope of full opening. However, the parallel choke manifold proposed in this paper, i.e. a program of parallel throttling, can enhance the accurate choking wellhead backpressure for MPD. The fine linear choking principle and feasibility of the parallel choke manifold were analyzed in detail by calculating the resistance modulus of bypass valves. The formula calculated the resistance modulus of each valve under different working state. Furthermore, the laboratory tests shown the parallel throttle method can achieve the control of fine choking pressure by switching one or more valves in the branch pipes. Therefore, the proposed parallel choke manifold system can reduce the requirements for the linear capability of valves and provide some references to further study the surface fine choking pressure system for MPD.

In order to apply smart card data in decision-making of public transportation planning and management, the paper researched estimating method of alighting bus stops of smart card passengers. Based on Trip-chain thought, the paper presented estimation algorithm applying the three hypotheses of “Next Trip”, “Last Trip” and “Return Trip”. Then, the algorithm was tested and analyzed using large-scale actual data of Advanced Public Transportation Systems of Nanning City in China. The results show that Trip-chain Method can estimate majority of alighting bus stops.

This study conducts investigations on the plants and plant landscaping in the two regions - Huangxing Commercial Pedestrian Street and Furong Road, which are representative and with relative concentration of population flow and traffic flow. The statistics results show that there are a total of 21 families and 25 species of ornamental plants applied in Huangxing Pedestrian Street, of which arbors and shrubs are widely used with 11 species of arbors, and 11 species of small arbors and shrubs; in terms of plant families, plants from Oleaceae, Pinaceae and Celastraceae families are more frequently used. There are a total of 12 families and 15 species of ornamental plants applied in the Furong Road, of which shrubs are more extensively used with 10 species; in terms of plant family and genera, plants from Oleaceae, Rosaceae and Theaceae families are more frequently used. On this basis, and combining with the different plant combinations and collocations, this paper conducts comparative analysis on the regional landscape arrangement modes and features, and points out the shortcomings of plant species richness and landscape levels in the plant landscapes of the two regions.

Current symbolic execution is challenged by its ability to deal with loops. The case gets worse for loops manipulating recursive data structures. In this paper, we extend classic symbolic execution techniques for error detection of programs manipulating lists in loops. The idea is to enhance the symbolic execution with the utilization of quantitative aspect of the shape, and to construct the exit state of the loop. The exit state is constrained by a set of numeric constraints containing normal symbolic variables in programs and instrumented symbolic variables on the shapes. A prototype tool has been implemented and experiments are conducted on some commonly used list manipulating programs.