A new method of numerical seismic stability safety evaluation for a rock slope is proposed based on the analysis of a gravity dam foundation subjected to earthquake loading. The shear strengths of the weak discontinui...A new method of numerical seismic stability safety evaluation for a rock slope is proposed based on the analysis of a gravity dam foundation subjected to earthquake loading. The shear strengths of the weak discontinuities are divided by different shear strength reduction ratios （K） and numerical seismic analysis is carried out after the static analysis is completed. With different K values, the curves of the permanent horizontal displacement of key points of the dam foundation （K-displacement curves） are studied. According to the curve change, the distribution of plastic zones in the foundation, and the slow convergence of the finite element method （FEM）, the seismic stability safety factor is defined as Kwhen the gravity dam is in the limit equilibrium state subjected to earthquake loading. These concepts were applied to the evaluation of seismic stability safety of a gravity dam for a hydropower project. The analysis of the example shows that the proposed method is feasible and is an effective method of seismic stability safety evaluation.展开更多
The Gravity Recovery and Climate Experiment（GRACE） mission can significantly improve our knowledge of the temporal variability of the Earth＇s gravity field.We obtained monthly gravity field solutions based on varia...The Gravity Recovery and Climate Experiment（GRACE） mission can significantly improve our knowledge of the temporal variability of the Earth＇s gravity field.We obtained monthly gravity field solutions based on variational equations approach from GPS-derived positions of GRACE satellites and K-band range-rate measurements.The impact of different fixed data weighting ratios in temporal gravity field recovery while combining the two types of data was investigated for the purpose of deriving the best combined solution.The monthly gravity field solution obtained through above procedures was named as the Institute of Geodesy and Geophysics（IGG） temporal gravity field models.IGG temporal gravity field models were compared with GRACE Release05（RL05） products in following aspects：（i） the trend of the mass anomaly in China and its nearby regions within 2005-2010; （ii） the root mean squares of the global mass anomaly during 2005-2010; （iii） time-series changes in the mean water storage in the region of the Amazon Basin and the Sahara Desert between 2005 and 2010.The results showed that IGG solutions were almost consistent with GRACE RL05 products in above aspects（i）-（iii）.Changes in the annual amplitude of mean water storage in the Amazon Basin were 14.7 ± 1.2 cm for IGG,17.1 ± 1.3 cm for the Centre for Space Research（CSR）,16.4 ± 0.9 cm for the GeoForschungsZentrum（GFZ） and 16.9 ± 1.2 cm for the Jet Propulsion Laboratory（JPL） in terms of equivalent water height（EWH）,respectively.The root mean squares of the mean mass anomaly in Sahara were 1.2 cm,0.9 cm,0.9 cm and 1.2 cm for temporal gravity field models of IGG,CSR,GFZ and JPL,respectively.Comparison suggested that IGG temporal gravity field solutions were at the same accuracy level with the latest temporal gravity field solutions published by CSR,GFZ and JPL.展开更多
The goal is to define Quantum Gravity Value by combination between our new concept about physics energy behaviour [1] and Einstein relativity’s Theory [2]. Our theory is based on the existence of a relationship betwe...The goal is to define Quantum Gravity Value by combination between our new concept about physics energy behaviour [1] and Einstein relativity’s Theory [2]. Our theory is based on the existence of a relationship between energy and vacuum! So it can be considered that the energy is a function of the vacuum ratio (v). Therefore, we can say that vacuum ratio constitutes a part of space-time. With simple mathematical formula, we can easily obtain the equation of the Energy Vacuum. This gives us the distribution of the energy Vacuum (E) into two parts are inversely proportional from our vacuum energy diagram, the effective energy that the sole responsible for Curvature of space-time fabric, and the lost energy that the responsible of the Gravitational waves [3]. From these equations, we can find that the relationship with Energy and Vacuum ratio is linear which are compatible with Quantum Mechanics laws and Maintains the energy conservation principle. It is also observed that the equations obtained through our theory are Combining relativity and Quantum Mechanics into one continuum. If we take the equations of our theory, we can easily obtain from Curvature of Space-Time Fabric, the Gravity value equation which equals to the square root of energy multiply times the square of the vacuum ratio. On other hand, a curvature matrix and a Time Dilation’s Circle are proposed, which gives us a new method to facilitate the calculations of the parameters involved in the Space-Time Curvature.展开更多
In this study,high-resolution Moho depth and average crustal V_(p)/V_(s) ratio distributions in northeast China were obtained through joint inversion of receiver functions and gravity data.The new joint inversion meth...In this study,high-resolution Moho depth and average crustal V_(p)/V_(s) ratio distributions in northeast China were obtained through joint inversion of receiver functions and gravity data.The new joint inversion method comprehensively considers the complementary imaging strengths of the receiver functions in the vertical direction and the gravity data in the lateral direction.To a certain extent,it can reduce the adverse effects of the receiver function data caused by the sedimentary layers of the basin,the inclination of the Moho,and the structure heterogeneity below the station.In preprocessing the receiver function data,a regularized virtual station network was constructed using the teleseismic receiver function waveform reconstruction method to improve the overall spatial resolution.To filter the gravity data,the velocity structure-guided gravity filtering method and gravity upward continuation were used for the shallower region above the Moho and the deeper region below the lithosphere,respectively.The newly obtained model shows that the Moho depths of the Hailar Basin,Erlian Basin,Sanjiang Basin,and Bohai Bay Basin are slightly shallower than those of the surrounding areas,while the Moho depths of the Greater Xing’an Range,Lesser Xing’an Range,and Zhangguangcai Range are slightly deeper.Compared with previous results,the refined Moho depth distribution obtained in this study has a better correspondence with topographic relief and basin boundaries,and the contrast is more evident across the north-south gravity gradient lineament(NSGL).In the eastern part of the Songliao Basin,the Moho is relatively shallow,and there is a high V_(p)/V_(s) ratio,which may have been caused by the intrusion of hot mantle materials into the crust induced by lateral extension of the Songliao Basin.The high V_(p)/V_(s) ratio of the crust below the Changbaishan volcanic area implies the existence of partial melting in the crust caused by upwelling hot mantle materials.展开更多
The application of thermal diodes,which allow heat to flow more readily in one direction than the other,is an important way to reduce energy consumption in buildings and enhance the battery heat dissipation of electri...The application of thermal diodes,which allow heat to flow more readily in one direction than the other,is an important way to reduce energy consumption in buildings and enhance the battery heat dissipation of electric vehicles.Depending on various factors including the specific design,materials used,and operating conditions,the convective thermal diode can exhibit the best thermal rectification effect in intended applications compared to the other thermal diodes.In this study,a novel convective thermal diode with a wick was proposed based on the phase change heat transfer mechanism.This design takes advantage of both capillary forces provided by the wick and gravity to achieve enhanced unidirectional heat transfer performance for the designed convective thermal diode.The effect of the filling liquid ratio on the thermal performance of the thermal diode was experimentally investigated,which was in good agreement with the theoretical analysis.The research findings showed that with an optimal liquid filling ratio of 140%,the thermal diode with a wick can achieve a better thermal rectification ratio when subjected to a lower heating power,and the maximum thermal rectification ratio of 21.76 was experimentally achieved when the heating power of the thermal diode was 40 W.展开更多
基金supported by the National Natural Science Foundation of China (Grant No. 90510017)
文摘A new method of numerical seismic stability safety evaluation for a rock slope is proposed based on the analysis of a gravity dam foundation subjected to earthquake loading. The shear strengths of the weak discontinuities are divided by different shear strength reduction ratios （K） and numerical seismic analysis is carried out after the static analysis is completed. With different K values, the curves of the permanent horizontal displacement of key points of the dam foundation （K-displacement curves） are studied. According to the curve change, the distribution of plastic zones in the foundation, and the slow convergence of the finite element method （FEM）, the seismic stability safety factor is defined as Kwhen the gravity dam is in the limit equilibrium state subjected to earthquake loading. These concepts were applied to the evaluation of seismic stability safety of a gravity dam for a hydropower project. The analysis of the example shows that the proposed method is feasible and is an effective method of seismic stability safety evaluation.
基金funded by the Major National Scientific Research Plan(2013CB733305,2012CB957703)the National Natural Science Foundation of China(41174066,41131067,41374087,41431070)
文摘The Gravity Recovery and Climate Experiment（GRACE） mission can significantly improve our knowledge of the temporal variability of the Earth＇s gravity field.We obtained monthly gravity field solutions based on variational equations approach from GPS-derived positions of GRACE satellites and K-band range-rate measurements.The impact of different fixed data weighting ratios in temporal gravity field recovery while combining the two types of data was investigated for the purpose of deriving the best combined solution.The monthly gravity field solution obtained through above procedures was named as the Institute of Geodesy and Geophysics（IGG） temporal gravity field models.IGG temporal gravity field models were compared with GRACE Release05（RL05） products in following aspects：（i） the trend of the mass anomaly in China and its nearby regions within 2005-2010; （ii） the root mean squares of the global mass anomaly during 2005-2010; （iii） time-series changes in the mean water storage in the region of the Amazon Basin and the Sahara Desert between 2005 and 2010.The results showed that IGG solutions were almost consistent with GRACE RL05 products in above aspects（i）-（iii）.Changes in the annual amplitude of mean water storage in the Amazon Basin were 14.7 ± 1.2 cm for IGG,17.1 ± 1.3 cm for the Centre for Space Research（CSR）,16.4 ± 0.9 cm for the GeoForschungsZentrum（GFZ） and 16.9 ± 1.2 cm for the Jet Propulsion Laboratory（JPL） in terms of equivalent water height（EWH）,respectively.The root mean squares of the mean mass anomaly in Sahara were 1.2 cm,0.9 cm,0.9 cm and 1.2 cm for temporal gravity field models of IGG,CSR,GFZ and JPL,respectively.Comparison suggested that IGG temporal gravity field solutions were at the same accuracy level with the latest temporal gravity field solutions published by CSR,GFZ and JPL.
文摘The goal is to define Quantum Gravity Value by combination between our new concept about physics energy behaviour [1] and Einstein relativity’s Theory [2]. Our theory is based on the existence of a relationship between energy and vacuum! So it can be considered that the energy is a function of the vacuum ratio (v). Therefore, we can say that vacuum ratio constitutes a part of space-time. With simple mathematical formula, we can easily obtain the equation of the Energy Vacuum. This gives us the distribution of the energy Vacuum (E) into two parts are inversely proportional from our vacuum energy diagram, the effective energy that the sole responsible for Curvature of space-time fabric, and the lost energy that the responsible of the Gravitational waves [3]. From these equations, we can find that the relationship with Energy and Vacuum ratio is linear which are compatible with Quantum Mechanics laws and Maintains the energy conservation principle. It is also observed that the equations obtained through our theory are Combining relativity and Quantum Mechanics into one continuum. If we take the equations of our theory, we can easily obtain from Curvature of Space-Time Fabric, the Gravity value equation which equals to the square root of energy multiply times the square of the vacuum ratio. On other hand, a curvature matrix and a Time Dilation’s Circle are proposed, which gives us a new method to facilitate the calculations of the parameters involved in the Space-Time Curvature.
基金supported by the National Key R&D Program of China(Grant No.2022YFF0800701)the National Natural Science Foundation of China(Grant No.U1839205)。
文摘In this study,high-resolution Moho depth and average crustal V_(p)/V_(s) ratio distributions in northeast China were obtained through joint inversion of receiver functions and gravity data.The new joint inversion method comprehensively considers the complementary imaging strengths of the receiver functions in the vertical direction and the gravity data in the lateral direction.To a certain extent,it can reduce the adverse effects of the receiver function data caused by the sedimentary layers of the basin,the inclination of the Moho,and the structure heterogeneity below the station.In preprocessing the receiver function data,a regularized virtual station network was constructed using the teleseismic receiver function waveform reconstruction method to improve the overall spatial resolution.To filter the gravity data,the velocity structure-guided gravity filtering method and gravity upward continuation were used for the shallower region above the Moho and the deeper region below the lithosphere,respectively.The newly obtained model shows that the Moho depths of the Hailar Basin,Erlian Basin,Sanjiang Basin,and Bohai Bay Basin are slightly shallower than those of the surrounding areas,while the Moho depths of the Greater Xing’an Range,Lesser Xing’an Range,and Zhangguangcai Range are slightly deeper.Compared with previous results,the refined Moho depth distribution obtained in this study has a better correspondence with topographic relief and basin boundaries,and the contrast is more evident across the north-south gravity gradient lineament(NSGL).In the eastern part of the Songliao Basin,the Moho is relatively shallow,and there is a high V_(p)/V_(s) ratio,which may have been caused by the intrusion of hot mantle materials into the crust induced by lateral extension of the Songliao Basin.The high V_(p)/V_(s) ratio of the crust below the Changbaishan volcanic area implies the existence of partial melting in the crust caused by upwelling hot mantle materials.
基金supported by the National Natural Science Foundation of China(Grant No.52208124)Hubei Provincial Key Research and Design Project(Grant No.2020BAB129)Scientific Research Foundation of Wuhan University of Technology(Grant No.40120237 and 40120551)。
文摘The application of thermal diodes,which allow heat to flow more readily in one direction than the other,is an important way to reduce energy consumption in buildings and enhance the battery heat dissipation of electric vehicles.Depending on various factors including the specific design,materials used,and operating conditions,the convective thermal diode can exhibit the best thermal rectification effect in intended applications compared to the other thermal diodes.In this study,a novel convective thermal diode with a wick was proposed based on the phase change heat transfer mechanism.This design takes advantage of both capillary forces provided by the wick and gravity to achieve enhanced unidirectional heat transfer performance for the designed convective thermal diode.The effect of the filling liquid ratio on the thermal performance of the thermal diode was experimentally investigated,which was in good agreement with the theoretical analysis.The research findings showed that with an optimal liquid filling ratio of 140%,the thermal diode with a wick can achieve a better thermal rectification ratio when subjected to a lower heating power,and the maximum thermal rectification ratio of 21.76 was experimentally achieved when the heating power of the thermal diode was 40 W.
