Among the triggering factors of postearthquake bedrock landslides, rainfall plays an important role. However, with slope variation, the mechanism of its effects on the failure of rock landslides is not dear. Here, fro...Among the triggering factors of postearthquake bedrock landslides, rainfall plays an important role. However, with slope variation, the mechanism of its effects on the failure of rock landslides is not dear. Here, from the viewpoint of fracture mechanics, and based on post-earthquake conditions, the mechanisms of crack propagation, water infiltration and development of the sliding surface were investigated. Then, according to the upper boundary theorem, the effects of water infiltrated into fractures on the stability of rock slopes were analyzed quantitatively. Finally, an example is presented to verify the theory. The results show that the propagation and coalescence of cracks and the lubrication of incipient sliding surfaces are the main causes of the failure of post-earthquake rock landslides in response to rainfall.展开更多
In nanoscale technology, transistor aging is one of the most critical problems that impact on the reliability of circuits. Aging sensor is a good online way to detect the circuit aging, which performs during the opera...In nanoscale technology, transistor aging is one of the most critical problems that impact on the reliability of circuits. Aging sensor is a good online way to detect the circuit aging, which performs during the operating time with no influence of the normal operation of circuits. In this paper, a Dou- ble-edge-triggered Detection Sensor for circuit Aging （DSDA） is proposed, which employs data signal of logic circuits as its clock to control the sampling process. The simulation is done by Hspice using 45 nm technology. The results show that this technique is not case of the detection precision is more than 80% under aging fault effectively with the 8% power cost and 30% sensitive to the process variations. The worst the different process variations. It can detect performance cost.展开更多
This paper presents an procedure for purifying training data sets （i.e., past occurrences of slope failures） for inverse estimation on unobserved trigger factors of ＂different types of simultaneous slope failures＂...This paper presents an procedure for purifying training data sets （i.e., past occurrences of slope failures） for inverse estimation on unobserved trigger factors of ＂different types of simultaneous slope failures＂. Due to difficulties in pixel-by-pixel observations of trigger factors, as one of the measures, the authors had proposed an inverse analysis algorithm on trigger factors based on SEM （structural equation modeling）. Through a measurement equation, the trigger factor is inversely estimated, and a TFI （trigger factor influence） map can be also produced. As a subsequence subject, a purification procedure of training data set should be constructed to improve the accuracy of TFI map which depends on the representativeness of given training data sets of different types of slope failures. The proposed procedure resamples the matched pixels between original groups of past slope failures （i.e., surface slope failures, deep-seated slope failures, landslides） and classified three groups by K-means clustering for all pixels corresponding to those slope failures. For all cases of three types of slope failures, the improvement of success rates with respect to resampled training data sets was confirmed. As a final outcome, the differences between TFI maps produced by using original and resampled training data sets, respectively, are delineated on a DIF map （difference map） which is useful for analyzing trigger factor influence in terms of ＂risky- and safe-side assessment＂ sub-areas with respect to ＂different types of simultaneous slope failures＂.展开更多
This paper calculates the static Coulomb stress changes generated by four earthquakes in the Yutian area during 2008 ~ 2014 separately,then discusses the triggering influence,their accumulated Coulomb stress changes a...This paper calculates the static Coulomb stress changes generated by four earthquakes in the Yutian area during 2008 ~ 2014 separately,then discusses the triggering influence,their accumulated Coulomb stress changes and their influence on nearby faults.The results indicate that the M S5.5 earthquake in 2011 and the M_S7.3 earthquake in 2014 are both in the regions where the Coulomb stress change is positive,the stress changes are 0.004 MPa and 0.021 MPa, respectively, meaning they are triggered by prior earthquakes.The M S6.2 earthquake in 2012 occurred in the place where Coulomb stress change was negative,so it is postponed by the prior earthquakes.The image of Coulomb stress changes of the M S7.3 earthquake in 2014 is in accord with aftershocks( M L≥ 3.0)distribution,but some regions on the fault where the Coulomb stress change is positive have few aftershocks,and strong aftershocks may occur at these districts in future.In addition,this paper calculates the Coulomb stress change on nearby faults,and finds that the Coulomb stress changes of different elements in the GGC fault are very different,and must receive strong triggered-influence,though the result may be influenced by the input finite fault model,so there is still a large earthquake-risk.The GGN,PLC,PLW and LBW faults were also triggered by the four earthquakes occurring between 2008 ~ 2014.Their maximum Coulomb stress changes all exceed 0.002 MPa,so they also have a strong earthquake hazard.展开更多
基金supported by The National Basic Research Program of China (also called 973 Program) (Grant No. 2008CB425802)the National Natural Science Foundation of China (Grant No. 40872181)
文摘Among the triggering factors of postearthquake bedrock landslides, rainfall plays an important role. However, with slope variation, the mechanism of its effects on the failure of rock landslides is not dear. Here, from the viewpoint of fracture mechanics, and based on post-earthquake conditions, the mechanisms of crack propagation, water infiltration and development of the sliding surface were investigated. Then, according to the upper boundary theorem, the effects of water infiltrated into fractures on the stability of rock slopes were analyzed quantitatively. Finally, an example is presented to verify the theory. The results show that the propagation and coalescence of cracks and the lubrication of incipient sliding surfaces are the main causes of the failure of post-earthquake rock landslides in response to rainfall.
基金Supported by the National Natural Science Foundation of China (No.61274036 and 61106038)Anhui Provincial Natural Science Foundation of China (No.090412034)
文摘In nanoscale technology, transistor aging is one of the most critical problems that impact on the reliability of circuits. Aging sensor is a good online way to detect the circuit aging, which performs during the operating time with no influence of the normal operation of circuits. In this paper, a Dou- ble-edge-triggered Detection Sensor for circuit Aging （DSDA） is proposed, which employs data signal of logic circuits as its clock to control the sampling process. The simulation is done by Hspice using 45 nm technology. The results show that this technique is not case of the detection precision is more than 80% under aging fault effectively with the 8% power cost and 30% sensitive to the process variations. The worst the different process variations. It can detect performance cost.
文摘This paper presents an procedure for purifying training data sets （i.e., past occurrences of slope failures） for inverse estimation on unobserved trigger factors of ＂different types of simultaneous slope failures＂. Due to difficulties in pixel-by-pixel observations of trigger factors, as one of the measures, the authors had proposed an inverse analysis algorithm on trigger factors based on SEM （structural equation modeling）. Through a measurement equation, the trigger factor is inversely estimated, and a TFI （trigger factor influence） map can be also produced. As a subsequence subject, a purification procedure of training data set should be constructed to improve the accuracy of TFI map which depends on the representativeness of given training data sets of different types of slope failures. The proposed procedure resamples the matched pixels between original groups of past slope failures （i.e., surface slope failures, deep-seated slope failures, landslides） and classified three groups by K-means clustering for all pixels corresponding to those slope failures. For all cases of three types of slope failures, the improvement of success rates with respect to resampled training data sets was confirmed. As a final outcome, the differences between TFI maps produced by using original and resampled training data sets, respectively, are delineated on a DIF map （difference map） which is useful for analyzing trigger factor influence in terms of ＂risky- and safe-side assessment＂ sub-areas with respect to ＂different types of simultaneous slope failures＂.
基金funded by the National Key Technology R&D Program of China(2012BAK19B02)
文摘This paper calculates the static Coulomb stress changes generated by four earthquakes in the Yutian area during 2008 ~ 2014 separately,then discusses the triggering influence,their accumulated Coulomb stress changes and their influence on nearby faults.The results indicate that the M S5.5 earthquake in 2011 and the M_S7.3 earthquake in 2014 are both in the regions where the Coulomb stress change is positive,the stress changes are 0.004 MPa and 0.021 MPa, respectively, meaning they are triggered by prior earthquakes.The M S6.2 earthquake in 2012 occurred in the place where Coulomb stress change was negative,so it is postponed by the prior earthquakes.The image of Coulomb stress changes of the M S7.3 earthquake in 2014 is in accord with aftershocks( M L≥ 3.0)distribution,but some regions on the fault where the Coulomb stress change is positive have few aftershocks,and strong aftershocks may occur at these districts in future.In addition,this paper calculates the Coulomb stress change on nearby faults,and finds that the Coulomb stress changes of different elements in the GGC fault are very different,and must receive strong triggered-influence,though the result may be influenced by the input finite fault model,so there is still a large earthquake-risk.The GGN,PLC,PLW and LBW faults were also triggered by the four earthquakes occurring between 2008 ~ 2014.Their maximum Coulomb stress changes all exceed 0.002 MPa,so they also have a strong earthquake hazard.
