A multi-block model and a corresponding computer program have been developed which predict the kinematics of landslides.Furthermore,a unique event for studying different models simulating the triggering and movement o...A multi-block model and a corresponding computer program have been developed which predict the kinematics of landslides.Furthermore,a unique event for studying different models simulating the triggering and movement of landslides is the 2008Wenchuan earthquake in the mountainous region in Sichuan Province of China,which caused a large number of rapid landslides.The purpose of the paper is two-fold:(a)to propose and incorporate into the multi-block model constitutive relations predicting soil response along slip surfaces,and(b)to apply the multi-block model with the constitutive relations at landslides triggered by the Wenchuan earthquake.The proposed constitutive equations predict the shape of the shear stress-displacement response measured in ring shear tests.In the application,four landslides caused by the Wenchuan earthquake were considered.Only in one of these landslides the shear resistance-displacement response along the slip surface has been measured in laboratory tests.At this landslide,the triggering and movement of the landslide was predicted.In the other landslides,back analyses were performed and it was observed that the multi-block model predicted reasonably well the final configuration of all slides.In addition,as the measured and back-estimated total friction angle of all landslides was less than 180,and the materials along the slip surface were sandy,it is inferred that some,or all of the slip surface during these slides was sheared in an undrained manner and excess pore pressures generated during sliding played a key role in the triggering and movement of these landslides.Concluding,the paper(A)proposed and validated a multi-block constitutive model which can be applied to predict the triggering and movement of earthquake-induced slides and(B)by analyzing four landslides of the 2008 Wenchuan earthquake,it concludes that some,or all of the slip surface during these slides,was sheared in an undrained manner and excess pore pressures generated during sliding played a key role in the triggering and movement of these landslides.展开更多
Chinese calligraphy is a thousand-year-old writing art. The question of how Chinese calligraphy artworks convey emotion has cast its spell over people for millennia. Calligraphers' joys and sorrows were expressed ...Chinese calligraphy is a thousand-year-old writing art. The question of how Chinese calligraphy artworks convey emotion has cast its spell over people for millennia. Calligraphers' joys and sorrows were expressed in the complexity of the character strokes, style variations and general layouts. Determining how Chinese calligraphy aesthetic patterns emerged from the general layout of artworks is a challenging objective for researchers. Here we investigate the statistical fluctuation structure of Chinese calligraphy characters sizes using characters obtained from the calligraphy artwork "Preface to the Poems Collected from the Orchid Pavilion" which was praised as the best running script under heaven. We found that the character size distribution is a stretched exponential distribution. Moreover, the variations in the local correlation features in character size fluctuations can accurately reflect expressions of the calligrapher's complex feelings. The fractal dimensions of character size fluctuations are close to the Fibonacci sequence. The Fibonacci number is first discovered in the Chinese calligraphy artworks, which inspires the aesthetics of Chinese calligraphy artworks and maybe also provides an approach to creating Chinese calligraphy artworks in multiple genres.展开更多
The geospatial distribution pattern in traditional Chinese settlements(TCSs)reflects the traditional harmony between humans and nature,which has been learned over centuries.However,TCSs have experienced serious distur...The geospatial distribution pattern in traditional Chinese settlements(TCSs)reflects the traditional harmony between humans and nature,which has been learned over centuries.However,TCSs have experienced serious disturbances by urbanization and migration.It is crucial to explore the local wisdom of geospatial patterns and dominant factors for TCSs at the national scale in China.This study sought to determine the geospatial wisdom of traditional settlements to enrich our future settlement development with the aim of establishing Chinese settlement values for modern living.Herein,a dataset of 4000 TCSs were analyzed and clustered for environmental factors that affect their geospatial patterns by machine learning algorithms.We concluded that(1)five geospatial patterns of TCSs were clustered on a national scale,and the threshold of environmental factors of TCS groups was detected.(2)Environmental conditions and settlement concepts interacted and determined the similarities and differences among TCS groups.(3)The key boundary for TCSs and the dominant factors for each zone were determined,and topographical conditions and hydrologic resources played significant roles in all five TCS zones.This study provides a better understanding of the adaptability of the environment in relation to the TCSs and aids in planning TCS conservation and rural revitalization.展开更多
The Gutenberg-Richter and Omori Laws, which are generally used to characterize the temporal distribution of aftershock, failed to reflect the statistic properties of climatic outbreak of aftershock energy. Based on a ...The Gutenberg-Richter and Omori Laws, which are generally used to characterize the temporal distribution of aftershock, failed to reflect the statistic properties of climatic outbreak of aftershock energy. Based on a new concept of magnitude clusters describing the fluctuation of aftershock energy release of the Wenchuan Earthquake, we discovered that the pattern of the continuous high-magnitude aftershock follows a power-law rather than a non-Poisson distribution. This suggests that the after-shocks with high magnitudes are statistically clustered. We then divided the aftershock sequences into three sections and demonstrated that though the probability of strong outbreaks decreased with time, there exists a high possibility of the occurrence of isolated high-magnitude aftershocks in the future. Based on self-organized criticality theory, the mechanisms of the power-law pattern of magnitude clusters are discussed. This discovery may be used to guide future aftershock predication and the associated post-disaster reconstruction.展开更多
基金The National Key R&D Program of China (2017YFC1502903) Sichuan International Cooperation and Exchange for Science and Technology (2016HH0079)+1 种基金 "Novel methodologies for the assessment of risk of ground displacement" under ESPA 2007-2013 of Greece under
文摘A multi-block model and a corresponding computer program have been developed which predict the kinematics of landslides.Furthermore,a unique event for studying different models simulating the triggering and movement of landslides is the 2008Wenchuan earthquake in the mountainous region in Sichuan Province of China,which caused a large number of rapid landslides.The purpose of the paper is two-fold:(a)to propose and incorporate into the multi-block model constitutive relations predicting soil response along slip surfaces,and(b)to apply the multi-block model with the constitutive relations at landslides triggered by the Wenchuan earthquake.The proposed constitutive equations predict the shape of the shear stress-displacement response measured in ring shear tests.In the application,four landslides caused by the Wenchuan earthquake were considered.Only in one of these landslides the shear resistance-displacement response along the slip surface has been measured in laboratory tests.At this landslide,the triggering and movement of the landslide was predicted.In the other landslides,back analyses were performed and it was observed that the multi-block model predicted reasonably well the final configuration of all slides.In addition,as the measured and back-estimated total friction angle of all landslides was less than 180,and the materials along the slip surface were sandy,it is inferred that some,or all of the slip surface during these slides was sheared in an undrained manner and excess pore pressures generated during sliding played a key role in the triggering and movement of these landslides.Concluding,the paper(A)proposed and validated a multi-block constitutive model which can be applied to predict the triggering and movement of earthquake-induced slides and(B)by analyzing four landslides of the 2008 Wenchuan earthquake,it concludes that some,or all of the slip surface during these slides,was sheared in an undrained manner and excess pore pressures generated during sliding played a key role in the triggering and movement of these landslides.
基金funded by the National Natural Science Foundation of China (No. 41465010, 41977245)。
文摘Chinese calligraphy is a thousand-year-old writing art. The question of how Chinese calligraphy artworks convey emotion has cast its spell over people for millennia. Calligraphers' joys and sorrows were expressed in the complexity of the character strokes, style variations and general layouts. Determining how Chinese calligraphy aesthetic patterns emerged from the general layout of artworks is a challenging objective for researchers. Here we investigate the statistical fluctuation structure of Chinese calligraphy characters sizes using characters obtained from the calligraphy artwork "Preface to the Poems Collected from the Orchid Pavilion" which was praised as the best running script under heaven. We found that the character size distribution is a stretched exponential distribution. Moreover, the variations in the local correlation features in character size fluctuations can accurately reflect expressions of the calligrapher's complex feelings. The fractal dimensions of character size fluctuations are close to the Fibonacci sequence. The Fibonacci number is first discovered in the Chinese calligraphy artworks, which inspires the aesthetics of Chinese calligraphy artworks and maybe also provides an approach to creating Chinese calligraphy artworks in multiple genres.
基金National Key Research and Development Program of China,No.2020YFD1100701Social Science Research“14th Five-Year Plan”2021 Project of Sichuan Province,No.SC21ST001Strategic Priority Research Program of the Chinese Academy of Sciences,No.XDA23090502。
文摘The geospatial distribution pattern in traditional Chinese settlements(TCSs)reflects the traditional harmony between humans and nature,which has been learned over centuries.However,TCSs have experienced serious disturbances by urbanization and migration.It is crucial to explore the local wisdom of geospatial patterns and dominant factors for TCSs at the national scale in China.This study sought to determine the geospatial wisdom of traditional settlements to enrich our future settlement development with the aim of establishing Chinese settlement values for modern living.Herein,a dataset of 4000 TCSs were analyzed and clustered for environmental factors that affect their geospatial patterns by machine learning algorithms.We concluded that(1)five geospatial patterns of TCSs were clustered on a national scale,and the threshold of environmental factors of TCS groups was detected.(2)Environmental conditions and settlement concepts interacted and determined the similarities and differences among TCS groups.(3)The key boundary for TCSs and the dominant factors for each zone were determined,and topographical conditions and hydrologic resources played significant roles in all five TCS zones.This study provides a better understanding of the adaptability of the environment in relation to the TCSs and aids in planning TCS conservation and rural revitalization.
基金supported by State Key Program of National Natural Science of China (Grant No. 41030742)Key Laboratory of Ecotourism’s Application Technology of Hunan Province (Grant No. 10STLVZD03)
文摘The Gutenberg-Richter and Omori Laws, which are generally used to characterize the temporal distribution of aftershock, failed to reflect the statistic properties of climatic outbreak of aftershock energy. Based on a new concept of magnitude clusters describing the fluctuation of aftershock energy release of the Wenchuan Earthquake, we discovered that the pattern of the continuous high-magnitude aftershock follows a power-law rather than a non-Poisson distribution. This suggests that the after-shocks with high magnitudes are statistically clustered. We then divided the aftershock sequences into three sections and demonstrated that though the probability of strong outbreaks decreased with time, there exists a high possibility of the occurrence of isolated high-magnitude aftershocks in the future. Based on self-organized criticality theory, the mechanisms of the power-law pattern of magnitude clusters are discussed. This discovery may be used to guide future aftershock predication and the associated post-disaster reconstruction.