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CBM extraction through horizontally connected wells realizes the connection of two wells by controlling well trajectory in coal seam, can effectively increase CBM flowing area, and improve CBM recovery of single well. It involves guiding while drilling, cavity making in seam, distant accurate connection, reservoir protection and other advanced technologies. The horizontal connected well engineering carried out by Xi’an Research Institute of China Coal Technology & Engineering Group Corp in Panzhuang block of Qinshui basin, which has successfully realized the distant connection of two wells by using wireless MWD, rotary magnetic distance and other tools as well as reasonable drilling technology, subsequent drainage and extraction effect was remarkable. The paper presents in detail the design, construction, drilling and development result of the connected wells.

The extended-reach horizontally-intersected well used to extract coalbed methane (CBM)can increase reservoir contact area, extend the influence scope of drainage-pressure drop and the district of CBM desorption. Furthermore, the extended-reach horizontally-intersected well can enhance unit well output and create favorable conditions for future workover. With the support of Major Projects of National Science and Technology, the research on key technologies of extended-reach horizontally-intersected well is done through theoretical analysis and experiment, the concrete research content includes selection of target formation and design of casing program, choice of survey instruments, research on the bottom hole assembly design and technique of steering wellpath, research on drilling fluid and extended-reach horizontally-intersected technology. As engineering examples of popularization and application of extended-reach horizontally-intersected well, a “U” shape well group located in Sihe mine field of Qinshui Basin and a “V” shape cluster well group located in Dafosi coal mine of Binchang mining area have been constructed successfully by using the integrated technologies.

By introducing the structure character and working principle of PDM, borehole technologies of PDM directional drilling were studied in this text, including borehole technology principle, directional method, technology flow, drilling technology parameters, branch borehole technology etc. Shaanxi Tingnan Coal .Ltd field application was taken as an example to do a simple introduction on PDM matching equipment and technology promotion. The borehole technology and related result can be used as reference for horizontal directional drilling research and construction.

Using GPS trajectories to recommend pick-up points for taxi driver comes to be a promising approach of increasing profits and decreasing pollutions. In the existing methods, nearly all the GPS data of a city are computed for recommendation. However, it is time-consuming and not accurate enough owing to too much spatio-temporal noise. Therefore, we propose a novel method of recommending pick-up for taxi driver based on spatio-temporal clustering. It is made up of data preprocessing and real-time recommendation. Firstly, we capture the historical pick-up points by analyzing their intervals. These points are clustered at different time and different regions to create candidate pick-up points. Secondly, after ranking the candidate pick-up points around the taxi, the top-5 valuable pick-up points are recommended for taxi drivers. The experimental results, whose data come from Microsoft Research Asia, show that our method can effectively recommend pick-up points for taxi drivers.