According to field investigation and interpretation of remote sensing images,the north segment of the Longling-Ruili fault is a Holocene dextral strike-slip fault with a small amount of normal faulting.Based on large-...According to field investigation and interpretation of remote sensing images,the north segment of the Longling-Ruili fault is a Holocene dextral strike-slip fault with a small amount of normal faulting.Based on large-scale geological mapping at some typical locations and quantitative geomorphologic deformation measurement and dating analysis,this fault is a Holocene active fault.The strike-slip rate of the Longling-Ruili fault is 2.2 ~2.5mm / a and vertical slip rate is 0.6mm /a since the late Pleistocene epoch.The strike-slip rate of the Longling-Ruili fault is 1.8~3.0mm /a and vertical slip rate is 0.5mm /a since the Holocene epoch.Based on the Poisson model,lognormal model and BPT model,the occurrence probability of strong earthquakes in 50 years is estimated to be 6.32%,0.08%and 0.05%,respectively.Then,a 1.82% probability of occurrence of characteristic earthquake for the north segment of the Longling-Ruili fault is obtained by setting a weight of 0.28,0.36 and 0.36 to the Poisson model,lognormal model and BPT model,respectively.展开更多
Carrying on a series of compression and shear tests by a large number of specimens, reliabilities of T300/QY8911 laminated composite were studied when dispersibility models were described. The results show that the st...Carrying on a series of compression and shear tests by a large number of specimens, reliabilities of T300/QY8911 laminated composite were studied when dispersibility models were described. The results show that the stress is linearly dependent on the strain and the damage modes of specimens are brittle fracture for both kinds of tests. Dispersibility models of compression and shear strength are expressed as Re-N（415.39, 6 586.36） and Rs-ln（5.071 8, 0.155 3）, respectively. When normal and lognormal distributions were used to describe the dispersibility models of compression and shear strength, and the compression or shear load follows the normal distribution, the almost same failure probability can be obtained from different reliability analysis methods.展开更多
The selectivity of gillnets for Oreochromis niloticus in Amerti reservoir （9°63′ N, 37°23′ E） was determined from gillnets with four mesh sizes （60, 80, 100 and 120 mm）. Four selectivity models （a nor...The selectivity of gillnets for Oreochromis niloticus in Amerti reservoir （9°63′ N, 37°23′ E） was determined from gillnets with four mesh sizes （60, 80, 100 and 120 mm）. Four selectivity models （a normal model assuming fixed spread, a normal model assuming that spread is proportional to mesh size, a lognormal model and a gamma model） were fitted to the data by using the share each length＇s catch total （SELECT） method. A total of 657 specimens of Oreochromis niloticus were caught （12.0-35.5 cm total length, TD. The sizes at first sexual maturity were 21.5 cm TL and 18.9 cm TL, respectively, for male and female Oreochromis niloticus. The lognormal selectivity curve provided the best fit to the data according to model deviance estimates with optimum selectivity of 16.66, 22.26, 27.78 and 33.38 cm TL for the 60, 80, 100 and 120 mm mesh sizes, respectively.展开更多
A probability based model of block failure capacity of pile foundation in clay soil under axial load is developed. The model was based on the first order second moment method. Instead of using point variability, the s...A probability based model of block failure capacity of pile foundation in clay soil under axial load is developed. The model was based on the first order second moment method. Instead of using point variability, the soil inherent variability is modelled as random field model. Based on this model, a reliability based factor of safety for designing pile group foundation, taking into account bock failure mechanism, is proposed. Furthermore, using simplified lognormal model, the relationship between the factor of safety used in design practice and target reliability may be derived explicitly.展开更多
基金sponsored by the Science and Technology Development Program of Ministry of Railways,PRC(2008G027-B)Special Program of Deep Exploration Techniques and Experimental Studies of Ministry of Land and Resources,PRC(Sinoprobe-06-04)
文摘According to field investigation and interpretation of remote sensing images,the north segment of the Longling-Ruili fault is a Holocene dextral strike-slip fault with a small amount of normal faulting.Based on large-scale geological mapping at some typical locations and quantitative geomorphologic deformation measurement and dating analysis,this fault is a Holocene active fault.The strike-slip rate of the Longling-Ruili fault is 2.2 ~2.5mm / a and vertical slip rate is 0.6mm /a since the late Pleistocene epoch.The strike-slip rate of the Longling-Ruili fault is 1.8~3.0mm /a and vertical slip rate is 0.5mm /a since the Holocene epoch.Based on the Poisson model,lognormal model and BPT model,the occurrence probability of strong earthquakes in 50 years is estimated to be 6.32%,0.08%and 0.05%,respectively.Then,a 1.82% probability of occurrence of characteristic earthquake for the north segment of the Longling-Ruili fault is obtained by setting a weight of 0.28,0.36 and 0.36 to the Poisson model,lognormal model and BPT model,respectively.
基金Project(51175424) supported by the National Natural Science FoundationProject(B07050) supported by the 111 Project,ChinaProject (JC20110257) supported by the Basic Research Foundation of Northwestern Polytechnical University
文摘Carrying on a series of compression and shear tests by a large number of specimens, reliabilities of T300/QY8911 laminated composite were studied when dispersibility models were described. The results show that the stress is linearly dependent on the strain and the damage modes of specimens are brittle fracture for both kinds of tests. Dispersibility models of compression and shear strength are expressed as Re-N（415.39, 6 586.36） and Rs-ln（5.071 8, 0.155 3）, respectively. When normal and lognormal distributions were used to describe the dispersibility models of compression and shear strength, and the compression or shear load follows the normal distribution, the almost same failure probability can be obtained from different reliability analysis methods.
文摘The selectivity of gillnets for Oreochromis niloticus in Amerti reservoir （9°63′ N, 37°23′ E） was determined from gillnets with four mesh sizes （60, 80, 100 and 120 mm）. Four selectivity models （a normal model assuming fixed spread, a normal model assuming that spread is proportional to mesh size, a lognormal model and a gamma model） were fitted to the data by using the share each length＇s catch total （SELECT） method. A total of 657 specimens of Oreochromis niloticus were caught （12.0-35.5 cm total length, TD. The sizes at first sexual maturity were 21.5 cm TL and 18.9 cm TL, respectively, for male and female Oreochromis niloticus. The lognormal selectivity curve provided the best fit to the data according to model deviance estimates with optimum selectivity of 16.66, 22.26, 27.78 and 33.38 cm TL for the 60, 80, 100 and 120 mm mesh sizes, respectively.
文摘A probability based model of block failure capacity of pile foundation in clay soil under axial load is developed. The model was based on the first order second moment method. Instead of using point variability, the soil inherent variability is modelled as random field model. Based on this model, a reliability based factor of safety for designing pile group foundation, taking into account bock failure mechanism, is proposed. Furthermore, using simplified lognormal model, the relationship between the factor of safety used in design practice and target reliability may be derived explicitly.
