稠密矢量场可视化有着广泛的应用。除了像箭线法、粒子追踪法这些标准方法外,基于纹理的可视化方法几乎能够展示矢量场中全部细节。我们提出了密集导向的流线算法,使用这个算法可以通过模拟卷积过程显示密集矢量场的方向、位置、局部流...稠密矢量场可视化有着广泛的应用。除了像箭线法、粒子追踪法这些标准方法外,基于纹理的可视化方法几乎能够展示矢量场中全部细节。我们提出了密集导向的流线算法,使用这个算法可以通过模拟卷积过程显示密集矢量场的方向、位置、局部流动速度。通过实验密集导向的流线算法比其他的L I C和F a s t L I C算法,生成的输出纹理速度更快。展开更多
The complex geological conditions in doubly complex areas tend to result in difficult surface survey operations and poor target layer imaging in the subsurface which has a great impact on seismic data quality. In this...The complex geological conditions in doubly complex areas tend to result in difficult surface survey operations and poor target layer imaging in the subsurface which has a great impact on seismic data quality. In this paper, we propose an optimal crooked line survey method for decreasing the surface survey operational difficulties and improving the sub-layer event continuity. The method concentrates on the surface shooting conditions, first, selecting the proper shot positions based on the specific surface topographic features to reduce the shot difficulties and then optimizing the receiver positioning to meet the prerequisite that the subsurface reflection points remain in a straight line. Using this method cannot only lower the shooting difficulty of rough surface condition areas but also overcome the subsurface reflection point bending problem appearing in the traditional crooked line survey method. On the other hand, we use local infill shooting rather than conventional overall infill shooting to improve sublayer event continuity and uniformity with lower survey operation cost. A model has been calculated and processed with the proposed optimal crooked line survey and local infill shooting design method workflow and the results show that this new method can work for seismic surveys in double complex areas.展开更多
In accordance with the requirements of the National Key Technology R&D Program of the 11th "Five-year Plan", a densified seismic network consisting of 26 seismic stations was established at the Three Gorges Reservo...In accordance with the requirements of the National Key Technology R&D Program of the 11th "Five-year Plan", a densified seismic network consisting of 26 seismic stations was established at the Three Gorges Reservoir area in the section of Hubei Province in March 2009 (21 short-period seismographs, 5 broadband digital seismographs). From March to December, 2009, a total of 2,995 ML -0. 8 - 2. 9 earthquakes were detected during the trial impounding of the Three Gorges Reservoir ( water level rose from 145 m to 172.8m). Using the double difference earthquake location algorithm, 2,837 earthquakes were precisely re-located. The results show that the pattern of small local earthquake swarms in the Three Gorges Reservoir area took on a linear distribution or mass-like cluster distribution, the mass-like clusters of events were generally within a distance of 5 km from waterfront, and the linear distribution of the earthquakes could be extended to a distance of 16 km away from the waterfront. In the Hubei section of the Three Gorges Reservoir, earthquakes were mainly concentrated in the northern end of the Xiannvshan and Jiuwanxi faults near the Xiangxihe River, and along the banks of the Yangtze River at the west of Xietan township and the Shenlongxi area on the northern bank in the Badong region, with focal depths less than 10km, and 4km in average. Earthquake frequency in the reservoir region had a positive correlation with reservoir water level fluctuations, indicating that the seismicity belongs to reservoir induced earthquakes. Along the Shenlong River in the reservoir area, earthquakes showed three linear distributions in the northern Badong county, and distributed according to Karst distribution. There are underground rivers in the carbonate strata. When the reservoir was impounded, water permeated into the underground rivers, thus inducing earthquakes. Earthquakes in the areas on the crossriver segment of Xiannvshan fault, the Jiuwanxi fault and at the areas west of Xietan, Shazhen and Xizhen, may be related to the softening of discontinuities, such as the Nukou fault, the Xiannvshan fault, or the bedding joints, which would lead to failure of rock masses, thus, inducing earthquakes. However, convincing conclusions about the triggering mechanism still need further study. Additionally, near the areas south of Wenhua and Yanglin of Zigui county and at Rangkou town east of Badong county, mininginduced earthquakes occurred at the mines nearby, and on the shores of the reservoir are some collapse earthquakes.展开更多
We consider a cooperative system consisting of a source node, a destination node, N (N 〉 1) wirelesspowered relays, and an eavesdropper. Each relay is assumed to be with a nonlinear energy harvester, in which there...We consider a cooperative system consisting of a source node, a destination node, N (N 〉 1) wirelesspowered relays, and an eavesdropper. Each relay is assumed to be with a nonlinear energy harvester, in which there exists a saturation threshold, limiting the level of the harvested power. For decode-and-forward and power splitting protocols, the Kth best relay is selected to assist the source-relay-destination transmission. An analytical expression for the secrecy outage probability is derived, and also verified by simulation.展开更多
文摘稠密矢量场可视化有着广泛的应用。除了像箭线法、粒子追踪法这些标准方法外,基于纹理的可视化方法几乎能够展示矢量场中全部细节。我们提出了密集导向的流线算法,使用这个算法可以通过模拟卷积过程显示密集矢量场的方向、位置、局部流动速度。通过实验密集导向的流线算法比其他的L I C和F a s t L I C算法,生成的输出纹理速度更快。
基金funded by the National Basic Research program of China(973 Program)(No.2009CB219403)Applied Basic Research Project of CNPC(No:2011B-3706)School Fund of SWPU,and Earth Exploration and Information Technology of Sichuan Provincial Key Disciplines Construction Program
文摘The complex geological conditions in doubly complex areas tend to result in difficult surface survey operations and poor target layer imaging in the subsurface which has a great impact on seismic data quality. In this paper, we propose an optimal crooked line survey method for decreasing the surface survey operational difficulties and improving the sub-layer event continuity. The method concentrates on the surface shooting conditions, first, selecting the proper shot positions based on the specific surface topographic features to reduce the shot difficulties and then optimizing the receiver positioning to meet the prerequisite that the subsurface reflection points remain in a straight line. Using this method cannot only lower the shooting difficulty of rough surface condition areas but also overcome the subsurface reflection point bending problem appearing in the traditional crooked line survey method. On the other hand, we use local infill shooting rather than conventional overall infill shooting to improve sublayer event continuity and uniformity with lower survey operation cost. A model has been calculated and processed with the proposed optimal crooked line survey and local infill shooting design method workflow and the results show that this new method can work for seismic surveys in double complex areas.
基金sponsored by the National Key Technology R&D Program (2008BAC38B04),China
文摘In accordance with the requirements of the National Key Technology R&D Program of the 11th "Five-year Plan", a densified seismic network consisting of 26 seismic stations was established at the Three Gorges Reservoir area in the section of Hubei Province in March 2009 (21 short-period seismographs, 5 broadband digital seismographs). From March to December, 2009, a total of 2,995 ML -0. 8 - 2. 9 earthquakes were detected during the trial impounding of the Three Gorges Reservoir ( water level rose from 145 m to 172.8m). Using the double difference earthquake location algorithm, 2,837 earthquakes were precisely re-located. The results show that the pattern of small local earthquake swarms in the Three Gorges Reservoir area took on a linear distribution or mass-like cluster distribution, the mass-like clusters of events were generally within a distance of 5 km from waterfront, and the linear distribution of the earthquakes could be extended to a distance of 16 km away from the waterfront. In the Hubei section of the Three Gorges Reservoir, earthquakes were mainly concentrated in the northern end of the Xiannvshan and Jiuwanxi faults near the Xiangxihe River, and along the banks of the Yangtze River at the west of Xietan township and the Shenlongxi area on the northern bank in the Badong region, with focal depths less than 10km, and 4km in average. Earthquake frequency in the reservoir region had a positive correlation with reservoir water level fluctuations, indicating that the seismicity belongs to reservoir induced earthquakes. Along the Shenlong River in the reservoir area, earthquakes showed three linear distributions in the northern Badong county, and distributed according to Karst distribution. There are underground rivers in the carbonate strata. When the reservoir was impounded, water permeated into the underground rivers, thus inducing earthquakes. Earthquakes in the areas on the crossriver segment of Xiannvshan fault, the Jiuwanxi fault and at the areas west of Xietan, Shazhen and Xizhen, may be related to the softening of discontinuities, such as the Nukou fault, the Xiannvshan fault, or the bedding joints, which would lead to failure of rock masses, thus, inducing earthquakes. However, convincing conclusions about the triggering mechanism still need further study. Additionally, near the areas south of Wenhua and Yanglin of Zigui county and at Rangkou town east of Badong county, mininginduced earthquakes occurred at the mines nearby, and on the shores of the reservoir are some collapse earthquakes.
基金Project supported by tile National High-Tech R&D Program (863) of China (No. 2015AA016304), the National Natural Sci- ence Foundation of China (Nos. 61401372 and 61531016), the Research Fund for the Doctoral Program of Higher Education of China (No. 20130182120017), the Natural Science Foundation of CQ CSTC (Nos. cstc2013jeyjA40040 and cstc2016jcyjA2002), the Postdoctoral Science Foundation of China (No. 2016M590875), and the Fundamental Research Funds for the Central Uni- versities, China (Nos. XDJK2014A017, XDJK2015B023, and XDJK2016A011)
文摘We consider a cooperative system consisting of a source node, a destination node, N (N 〉 1) wirelesspowered relays, and an eavesdropper. Each relay is assumed to be with a nonlinear energy harvester, in which there exists a saturation threshold, limiting the level of the harvested power. For decode-and-forward and power splitting protocols, the Kth best relay is selected to assist the source-relay-destination transmission. An analytical expression for the secrecy outage probability is derived, and also verified by simulation.