With waveform data of 613 earthquakes with ML ≥ 2. 5 in the middle section of the Xiaojiang fault and its adjacent area which occurred during January,1998 to September 2007,focal mechanisms were calculated by the dir...With waveform data of 613 earthquakes with ML ≥ 2. 5 in the middle section of the Xiaojiang fault and its adjacent area which occurred during January,1998 to September 2007,focal mechanisms were calculated by the direct wave amplitude ratio of S /P in the vertical component and their characteristics were analyzed. According to regional tectonic features of the middle section of the Xiaojiang fault and its adjacent area,the study region was partitioned into two zones with the Xiaojiang fault as the boundary,e. g. zone A and zone B (including the Xiaojiang fault). In order to research the faults stress in detail,the Xiaojiang fault zone was picked out for independent analysis. The study region was also partitioned into 1°× 1° cells with a 0. 5° step. The stress fields of zone A,B and the fault zone were inverted with the FMSI method (Gephart,1990). The results show that first, the faults are mainly of strike-slip in the middle section and its adjacent area,amounting to 81. 28%,69. 23% and 72. 97% in the A,B and fault zones,respectively. Secondly,the stress inversion also indicates that the directions of maximum principal stress σ1 in the A, B,and fault zones are approximately NNW,NWW and NWW,the stress action is mainly horizontal,and strike-slip faulting is dominant in the study area. On the other hand,the direction of the principal stress field in the central Yunnan block changed from NNW to NWW,however,in the region between the Yuanmou and Pudu River faults,the azimuth of the main compressive stress shows that the north-south slip is obvious. While the direction of the main compressive stress of the Xiaojiang fault zone is nearly NW; in the east of the Xiaojiang fault,the direction of principal compressive stress is NW to NNW in the eastern Yunnan block.展开更多
Fish assemblage structure in the hypoxic zone in the Changjiang (Yangtze River) estuary and its adjacent waters were analyzed based on data from bottom trawl surveys conducted on the R/V Beidou in June, August and Oct...Fish assemblage structure in the hypoxic zone in the Changjiang (Yangtze River) estuary and its adjacent waters were analyzed based on data from bottom trawl surveys conducted on the R/V Beidou in June, August and October 2006. Four fish assemblages were identified in each survey using two-way indicator species analysis (TWIA). High fish biomass was found in the northern part, central part and coastal waters of the survey area; in contrast, high fish diversity was found in the southern part of the survey area and the Changjiang estuary outer waters. Therefore, it is difficult to maintain high fishery production when high fish diversity is evenly distributed in the fish community. Fish became smaller and fish size spectra tended to be narrower because of fish species variations and differences in growth characteristics. Fish diversity increased, the age to maturity was reduced and some migrant species were not collected in the surveys. Fish with low economic value, small size, simple age structure and low tropic level were predominant in fish assemblages in the Changjiang estuary and its adjacent waters. The lowest hypoxic value decreased in the Changjiang estuary and its adjacent waters.展开更多
The territory of the Republic of Macedonia is divided to geographical regions, in which different types of monuments and houses from Ottoman character can be found. The monuments and regions presented through this pap...The territory of the Republic of Macedonia is divided to geographical regions, in which different types of monuments and houses from Ottoman character can be found. The monuments and regions presented through this paper do not cover all the regions of Macedonia but only the territories of Skopje, the capital of Macedonia and Ohrid. This paper involves a research of Ottoman housing and settlements in Macedonia according to the architectural characteristics and settlement textures using old-new photographs, related literature, internet sources and site investigation. The rich vernacular traditions we inherited from Ottoman ancestors would be a source for inspiring the architects in establishing the guiding principles for new buildings in Macedonia. Finally, this study concludes with some ways forward on how to attain cultural continuity for achieving sustainable development in the long run.展开更多
This paper presents a region-based method for extraction of consistent surfaces from raw point clouds. The method uses a new robust estimation method of constructing seed regions and a new method of orientating region...This paper presents a region-based method for extraction of consistent surfaces from raw point clouds. The method uses a new robust estimation method of constructing seed regions and a new method of orientating regions or surfaces. The robust estima- tion method selects good seed regions from candidate regions generated randomly in a structured neighborhood. The orienta- tion method uses transition vectors from which include angles of adjacent normal vectors are not greater than 90~ and thus can be orientated correctly crossing sharp features or close-by opposite surfaces. The region-based method consists of two levels of segmentation： planar segmentation and quadric segmentation, both of which produce consistent surfaces. The quadric segmen- tation fits general quadrics by 3 L fitting algorithm in its region growing process and can take consistent planar surfaces as ini- tials. Experimental results show that the robust estimation method has higher probability of success than the traditional one and the orientation method works well. Experimental results also demonstrate the applicability of our method to various data.展开更多
基金sponsored by the National Key Technology R&D Program (2006BAC1B03-03-01),Chinathe Joint Earthquake Science Foundation(A07058),China
文摘With waveform data of 613 earthquakes with ML ≥ 2. 5 in the middle section of the Xiaojiang fault and its adjacent area which occurred during January,1998 to September 2007,focal mechanisms were calculated by the direct wave amplitude ratio of S /P in the vertical component and their characteristics were analyzed. According to regional tectonic features of the middle section of the Xiaojiang fault and its adjacent area,the study region was partitioned into two zones with the Xiaojiang fault as the boundary,e. g. zone A and zone B (including the Xiaojiang fault). In order to research the faults stress in detail,the Xiaojiang fault zone was picked out for independent analysis. The study region was also partitioned into 1°× 1° cells with a 0. 5° step. The stress fields of zone A,B and the fault zone were inverted with the FMSI method (Gephart,1990). The results show that first, the faults are mainly of strike-slip in the middle section and its adjacent area,amounting to 81. 28%,69. 23% and 72. 97% in the A,B and fault zones,respectively. Secondly,the stress inversion also indicates that the directions of maximum principal stress σ1 in the A, B,and fault zones are approximately NNW,NWW and NWW,the stress action is mainly horizontal,and strike-slip faulting is dominant in the study area. On the other hand,the direction of the principal stress field in the central Yunnan block changed from NNW to NWW,however,in the region between the Yuanmou and Pudu River faults,the azimuth of the main compressive stress shows that the north-south slip is obvious. While the direction of the main compressive stress of the Xiaojiang fault zone is nearly NW; in the east of the Xiaojiang fault,the direction of principal compressive stress is NW to NNW in the eastern Yunnan block.
基金Supported by the National Natural Science Foundation of China (No. 30490233, 40906086)the National Basic Research Program of China (973 Program) (No. 2006CB400608)Taishan Scholar Program of Shandong Province, Postdoctoral creative foundation of Shandong Province and the Yellow & Bohai Sea Scientific Observation and Experiment Station for Fishery Resources and Environment, Ministry of Agriculture
文摘Fish assemblage structure in the hypoxic zone in the Changjiang (Yangtze River) estuary and its adjacent waters were analyzed based on data from bottom trawl surveys conducted on the R/V Beidou in June, August and October 2006. Four fish assemblages were identified in each survey using two-way indicator species analysis (TWIA). High fish biomass was found in the northern part, central part and coastal waters of the survey area; in contrast, high fish diversity was found in the southern part of the survey area and the Changjiang estuary outer waters. Therefore, it is difficult to maintain high fishery production when high fish diversity is evenly distributed in the fish community. Fish became smaller and fish size spectra tended to be narrower because of fish species variations and differences in growth characteristics. Fish diversity increased, the age to maturity was reduced and some migrant species were not collected in the surveys. Fish with low economic value, small size, simple age structure and low tropic level were predominant in fish assemblages in the Changjiang estuary and its adjacent waters. The lowest hypoxic value decreased in the Changjiang estuary and its adjacent waters.
文摘The territory of the Republic of Macedonia is divided to geographical regions, in which different types of monuments and houses from Ottoman character can be found. The monuments and regions presented through this paper do not cover all the regions of Macedonia but only the territories of Skopje, the capital of Macedonia and Ohrid. This paper involves a research of Ottoman housing and settlements in Macedonia according to the architectural characteristics and settlement textures using old-new photographs, related literature, internet sources and site investigation. The rich vernacular traditions we inherited from Ottoman ancestors would be a source for inspiring the architects in establishing the guiding principles for new buildings in Macedonia. Finally, this study concludes with some ways forward on how to attain cultural continuity for achieving sustainable development in the long run.
基金supported by the National Natural Science Foundation of China(Grant No.51205332)the SRF for the Returned Overseas Chinese Scholars
文摘This paper presents a region-based method for extraction of consistent surfaces from raw point clouds. The method uses a new robust estimation method of constructing seed regions and a new method of orientating regions or surfaces. The robust estima- tion method selects good seed regions from candidate regions generated randomly in a structured neighborhood. The orienta- tion method uses transition vectors from which include angles of adjacent normal vectors are not greater than 90~ and thus can be orientated correctly crossing sharp features or close-by opposite surfaces. The region-based method consists of two levels of segmentation： planar segmentation and quadric segmentation, both of which produce consistent surfaces. The quadric segmen- tation fits general quadrics by 3 L fitting algorithm in its region growing process and can take consistent planar surfaces as ini- tials. Experimental results show that the robust estimation method has higher probability of success than the traditional one and the orientation method works well. Experimental results also demonstrate the applicability of our method to various data.
