t Research and development of safe and effective control technology of hard roof is an inevitable trend at present. Directional hydraulic fracturing technology is expected to become a safe and effective way to control...t Research and development of safe and effective control technology of hard roof is an inevitable trend at present. Directional hydraulic fracturing technology is expected to become a safe and effective way to control and manage hard roof. In order to make hard roof fracture in a directional way, a hydraulic fracture field test has been conducted in the third panel district of Tashan Coal Mine in Datong. First, two hydraulic fracturing drilling holes and four observing drilling holes were arranged in the roof, followed by a wedge-shaped ring slot in each hydraulic fracturing drilling hole. The hydraulic fracturing holes were then sealed and, hydraulic fracturing was conducted. The results show that the hard roof is fractured directionally by the hydraulic fracturing function of the two fracturing drilling holes; the sudden drop, or the overall downward trend of hydraulic pressure from hydraulic monitoring is the proof that the rock in the hard roof has been fractured. The required hydraulic pressure to fracture the hard roof in Tashan coal mine, consisting of carboniferous sandstone layer, is 50.09 MPa, and the fracturing radius of a single drilling hole is not less than 10.5 m. The wedge-shaped ring slot made in the bottom of the hydraulic fracturing drilling hole plays a guiding role for crack propagation. After the hydraulic fracturing drill hole is cracked, the propagation of the resulting hydraulic crack, affected mainly by the regional stress field, will turn to other directions.展开更多
Based on the immune mechanics and multi-agent technology, a multi-agent artificial immune network (Maopt-aiNet) algorithm is introduced. Maopt-aiNet makes use of the agent ability of sensing and acting to overcome pre...Based on the immune mechanics and multi-agent technology, a multi-agent artificial immune network (Maopt-aiNet) algorithm is introduced. Maopt-aiNet makes use of the agent ability of sensing and acting to overcome premature problem, and combines the global and local search in the searching process. The performance of the proposed method is examined with 6 benchmark problems and compared with other well-known intelligent algorithms. The experiments show that Maopt-aiNet outperforms the other algorithms in these benchmark functions. Furthermore, Maopt-aiNet is applied to determine the Murphree efficiency of distillation column and satisfactory results are obtained.展开更多
基金Supported by the National Natural Science Foundation of China （51274194, 51004104） the Program for New Century Excellent Talents in University （NCET- 12-0958）
文摘t Research and development of safe and effective control technology of hard roof is an inevitable trend at present. Directional hydraulic fracturing technology is expected to become a safe and effective way to control and manage hard roof. In order to make hard roof fracture in a directional way, a hydraulic fracture field test has been conducted in the third panel district of Tashan Coal Mine in Datong. First, two hydraulic fracturing drilling holes and four observing drilling holes were arranged in the roof, followed by a wedge-shaped ring slot in each hydraulic fracturing drilling hole. The hydraulic fracturing holes were then sealed and, hydraulic fracturing was conducted. The results show that the hard roof is fractured directionally by the hydraulic fracturing function of the two fracturing drilling holes; the sudden drop, or the overall downward trend of hydraulic pressure from hydraulic monitoring is the proof that the rock in the hard roof has been fractured. The required hydraulic pressure to fracture the hard roof in Tashan coal mine, consisting of carboniferous sandstone layer, is 50.09 MPa, and the fracturing radius of a single drilling hole is not less than 10.5 m. The wedge-shaped ring slot made in the bottom of the hydraulic fracturing drilling hole plays a guiding role for crack propagation. After the hydraulic fracturing drill hole is cracked, the propagation of the resulting hydraulic crack, affected mainly by the regional stress field, will turn to other directions.
基金Supported by the National Natural Science Foundation of China (61271137)Public Science and Technology Research Funds Projects of Zhejiang Province (2011C21077)the Natural Science Foundation of Ningbo City (2011A610173)
文摘Based on the immune mechanics and multi-agent technology, a multi-agent artificial immune network (Maopt-aiNet) algorithm is introduced. Maopt-aiNet makes use of the agent ability of sensing and acting to overcome premature problem, and combines the global and local search in the searching process. The performance of the proposed method is examined with 6 benchmark problems and compared with other well-known intelligent algorithms. The experiments show that Maopt-aiNet outperforms the other algorithms in these benchmark functions. Furthermore, Maopt-aiNet is applied to determine the Murphree efficiency of distillation column and satisfactory results are obtained.
