The load profile is a key characteristic of the power grid and lies at the basis for the power flow control and generation scheduling.However,due to the wide adoption of internet-of-things(IoT)-based metering infrastr...The load profile is a key characteristic of the power grid and lies at the basis for the power flow control and generation scheduling.However,due to the wide adoption of internet-of-things(IoT)-based metering infrastructure,the cyber vulnerability of load meters has attracted the adversary’s great attention.In this paper,we investigate the vulnerability of manipulating the nodal prices by injecting false load data into the meter measurements.By taking advantage of the changing properties of real-world load profile,we propose a deeply hidden load data attack(i.e.,DH-LDA)that can evade bad data detection,clustering-based detection,and price anomaly detection.The main contributions of this work are as follows:(i)We design a stealthy attack framework that exploits historical load patterns to generate load data with minimal statistical deviation from normalmeasurements,thereby maximizing concealment;(ii)We identify the optimal time window for data injection to ensure that the altered nodal prices follow natural fluctuations,enhancing the undetectability of the attack in real-time market operations;(iii)We develop a resilience evaluation metric and formulate an optimization-based approach to quantify the electricity market’s robustness against DH-LDAs.Our experiments show that the adversary can gain profits from the electricity market while remaining undetected.展开更多
Deeply buried mountain tunnels are often exposed to the risk of rock bursts,which always cause serious damage to the supporting structures and threaten the safety of the engineers.Due to the limited data available,a s...Deeply buried mountain tunnels are often exposed to the risk of rock bursts,which always cause serious damage to the supporting structures and threaten the safety of the engineers.Due to the limited data available,a suitable approach to predict the rockburst tendency at the preliminary stage becomes very important.In this study,an integrated methodology combining 3D initial stress inversion and rockburst tendency prediction was developed and subsequently applied to a case study of the Sangzhuling Tunnel on the Sichuan–Tibet Railway.The numerical modelling involved inverting the initial stress field using a multiple linear regression method.The tunnel excavation was simulated separately by FDM and DEM,based on a stress boundary condition from the inverted stress field.The comparative analysis demonstrates that the rockburst ratio calculated using DEM(76.70%)exhibits a slight increase compared to FDM(75.38%),and the rockburst location is consistent with the actual situation.This suggests that DEM is more suitable for simulating the stress redistribution during excavation in a jointed rock mass.The numerical simulation combined with the deviatoric stress approach effectively predicts rockburst tendency,meeting the engineering requirements.Despite its limitations,numerical simulation remains a reliable method for predicting rock bursts.展开更多
Rock–soil aggregate landslides(RSALs) are a common geological hazard in deeply incised valleys in southwestern China. Large-scale RSALs are widely distributed in the upper reaches of the Dadu River, Danba County, Sic...Rock–soil aggregate landslides(RSALs) are a common geological hazard in deeply incised valleys in southwestern China. Large-scale RSALs are widely distributed in the upper reaches of the Dadu River, Danba County, Sichuan Province, and are influenced by slope structure, which can be divided into open, lock, strip, and dumbbell types, as well as soil type and meso-structure, which can be classified as layered rock–soil aggregate, block-soil, and grainsoil. In this study, the evolution of four types of structures, such as layered-dumbbell, block-soil lock, banded block-soil, and block-soil open types, were analyzed by field surveys, surface and deep displacement monitoring, and Flac3 D. It was found that the Danba reach of the Dadu River showed incised valley through the evolution from wide to slow valley affected by internal and external geological processes since the Quaternary Glaciation. In the layered-dumbbell rock–soil aggregate, the main sliding pattern is multi-stage sliding at different depths. Circular sliding in the trailing edge and plane sliding along the bedrock in the front edge body occurin the block-soil-lock type aggregate. Large-scale multi-level and circular sliding over long distances occur in the banded block-soil aggregate. The blocksoil open type is stable, with only circular sliding occurring in local and shallow surfaces of the body. The monitoring and numerical simulation results further show that slope structure and regularity have diversified with RSALs. The results provide a basis for analyzing the stability mechanism of RSALs and preventing RSALs in deeply incised valleys.展开更多
The response of dynamic wave pressures on structures would be more complicated and bring about new phenomena under the dynamic interaction between soil and structure. In order to better understand the response charact...The response of dynamic wave pressures on structures would be more complicated and bring about new phenomena under the dynamic interaction between soil and structure. In order to better understand the response characteristics on deeply embedded large cylindrical structures under random waves, and accordingly to offer valuable findings for engineering, the authors designed wave flume experiments to investigate comparatively dynamic wave pressures on a single and on continuous cylinders with two different embedment depths in response to two wave spectra.The time histories of the water surface elevation and the corresponding dynamic wave pressures exerted on the cylinder were analyzed in the frequency domain. By calculating the transfer function and spectral density for dynamic wave pressures along the height and around the circumference of the cylinder, experimental results of the single cylinder were compared with the theoretical results based on the linear diffraction theory, and detailed comparisons were also carried out between the single and continuous cylinders. Some new findings and the corresponding analysis are reported in present paper. The investigation on continuous cylinders will be used in particular for reference in engineering applications because information is scarce on studying such kind of problem both analytically and experimentally.展开更多
Due to the extreme complexity of mechanical response of soft surrounding rock(SR) around a tunnel under high geostatic stress conditions, the integration of physical and numerical modeling techniques was adopted. Base...Due to the extreme complexity of mechanical response of soft surrounding rock(SR) around a tunnel under high geostatic stress conditions, the integration of physical and numerical modeling techniques was adopted. Based on the similarity theory, new composite-similar material was developed, which showed good agreement with the similarity relation and successfully simulated physico-mechanical properties(PMP) of deep buried soft rock. And the 800 mm×800 mm×200 mm physical model(PM) was conducted, in which the endoscopic camera technique was adopted to track the entire process of failure of the model all the time. The experimental results indicate that the deformation of SR around a underground cavern possessed the characteristics of development by stages and in delay, and the initial damage of SR could induce rapid failure in the later stage, and the whole process could be divided into three stages, including the localized extension of crack(the horizontal load(HL) was in the range of 130 k N to 170 k N, the vertical load(VL) was in the range of 119 k N to 153.8 k N), rapid crack coalescence(the HL was in the range of 170 k N to 210 k N, the VL was in the range of 153.8 k N to 182.5 k N) and residual strength(the HL was greater than 210 k N, the VL was greater than 182.5 k N). Under the high stress conditions, the phenomenon of deformation localization in the SR became serious and different space positions show different deformation characteristics. In order to further explore the deformation localization and progressive failure phenomenon of soft SR around the deeply buried tunnel, applying the analysis software of FLAC3 D three-dimensional explicit finite-difference method, based on the composite strain-softening model of Mohr-Coulomb shear failure and tensile failure, the calculation method of large deformation was adopted. Then, the comparative analysis between the PM experiment and numerical simulation of the three centered arch tunnels was implemented and the relationship of deformation localization and progressive failure of SR around a tunnel under high stress conditions was discussed.展开更多
Based on the characteristics of surrounding rocks for deeply inclined roadway affected by argillation and water seepage, a structure model of layer crack plate was established to analyze the shear sliding instability ...Based on the characteristics of surrounding rocks for deeply inclined roadway affected by argillation and water seepage, a structure model of layer crack plate was established to analyze the shear sliding instability mechanism. Through solid mechanics analysis of anchored surrounding rock with defect from water seepage, combined with numerical analysis for instability mechanism under water seepage in deeply inclined roadway, key factors were proposed. Results show that with increasing height of layer crack plate, lateral buckling critical load value for high wall of the roadway decreases; there is a multistage distribution for tensile stress along the anchor bolt with defect under pulling state condition;groundwater seepage seriously affects the strength of surrounding rock of the roadway, to some extent the plastic zone of the high side rises up to 8 m. Finally some support strategies were proposed for the inclined roadway and successfully applied to Haoyuan coal mine in Tiela mining area,western China.展开更多
许多字典和书籍都把be deeply in debt译成"债台高筑",一直以来,这已成为一个约定俗成的译法。然而,从隐喻特别是容器隐喻的角度看,英文与中文是两种完全不同的意象:be deeply in debt是陷入其中,而"债台高筑"则是...许多字典和书籍都把be deeply in debt译成"债台高筑",一直以来,这已成为一个约定俗成的译法。然而,从隐喻特别是容器隐喻的角度看,英文与中文是两种完全不同的意象:be deeply in debt是陷入其中,而"债台高筑"则是凸起于地面上。本文通过分析be-in-something关系的容器隐喻及其已有的对应翻译,力求找到be deeply in debt的新译文。展开更多
Recent high-resolution deep seismic reflection profile across the Kunlun fault in northeastern Tibet shows clearly that the Moho is cut off by a complex thrust fault system. Moho offset is a general phenomenon, but li...Recent high-resolution deep seismic reflection profile across the Kunlun fault in northeastern Tibet shows clearly that the Moho is cut off by a complex thrust fault system. Moho offset is a general phenomenon, but little is known about the dynamic mechanism. In this study, contact models with Maxwell materials are used to simulate the mechanical process of Moho offset induced by the aseismic slip of deeply buried faults. Based on the seismic reflection data, we project a single fault model and a complex fault system model with two faults inter- secting. The deformations of the Moho, the aseismic slips, and contact stresses on faults in different models are discussed in detail. Results show that the Moho offset might be produced by aseismic slip of deeply buried faults, and the magnitude is influenced by the friction coefficient of faults and the viscosity of the lower crust. The maximum slip occurs near the Moho on the single fault or at the crossing point of two intersecting faults system. Stress concentrates mainly on the Moho, the deep end of faults, or the crossing point. This study will throw light on understanding the mechanism of Moho offset and aseismic slip of deeply buried faults. The results of complex fault system with two faults intersecting are also useful to understand the shallow intersecting faults that may cause earthquakes.展开更多
Organic-inorganic interactions between hydrocarbons and most minerals in deeply buried reservoirs remain unclear.In this study,gold capsules and fused silica capillary capsules(FSCCs)with different com-binations of nC...Organic-inorganic interactions between hydrocarbons and most minerals in deeply buried reservoirs remain unclear.In this study,gold capsules and fused silica capillary capsules(FSCCs)with different com-binations of nC_(16)H_(34),water(distilled water,CaCl_(2) water)and minerals(quartz,feldspar,calcite,kaolinite,smectite,and illite)were heated at 340℃ for 3-10 d,to investigate the evolution and reaction pathways of the organic-inorganic interactions in different hot systems.After heating,minerals exhibited little alteration in the anhydrous systems.Mineral alterations,how-ever,occurred obviously in the hydrous systems.Different inorganic components affected nC_(16)H_(34) degra-dation differently.Overall,water promoted the free-radical thermal-cracking reaction and step oxidation reaction but suppressed the free-radical cross-linking reaction.The impact of CaCl_(2) water on the nC_(16)H_(34) degradation was weaker than the distilled water as high Ca^(2+)concentration suppressed the formation of free radicals.The presence of different waters also affects the impact of different minerals on nC_(16)H_(34) degradation,via its impact on mineral alterations.In the anhydrous nC_(16)H_(34)-mineral systems,calcite and clays catalyzed generation of low-molecular-weight(LMW)alkanes,particularly the clays.Quartz,feldspar,and calcite catalyzed generation of high-molecular-weight(HMW)alkanes and PAHs,whereas clays catalyzed the generation of LMW alkanes and mono-bicyclic aromatic hydrocarbons(M-BAHs).In the hydrous nC_(16)H_(34)-distilled water-mineral systems,all minerals but quartz promoted nC_(16)H_(34) degra-dation to generate more LMW alkanes,less HMW alkanes and PAHs.In the nC_(16)H_(34)-CaCl_(2) water-mineral systems,the promotion impact of minerals was weaker than that in the systems with distilled water.This study demonstrated the generation of different hydrocarbons with different fluorescence colors in the different nC_(16)H_(34)-water-mineral systems after heating for the same time,implying that fluorescence colors need to be interpreted carefully in investigation of hydrocarbon charging histories and oil origins in deeply buried reservoirs.Besides,the organic-inorganic interactions in different nC_(16)H_(34)-water-mineral systems proceeded in different pathways at different rates,which likely led to preservation of liquid hydrocarbons at different depth(temperature).Thus,quantitative investigations of the reaction kinetics in different hydrocarbon-water-rock systems are required to improve the prediction of hydrocar-bon evolution in deeply buried hydrocarbon reservoirs.展开更多
有一种思念可以很长,有一种记忆可以很久,有一双手始终舒适,有一种情永远延续……It is a peaceful night again,everything is quiet.The moonlight shines brightly,which looks like pour-ing water and the cool wind flows through...有一种思念可以很长,有一种记忆可以很久,有一双手始终舒适,有一种情永远延续……It is a peaceful night again,everything is quiet.The moonlight shines brightly,which looks like pour-ing water and the cool wind flows through the window,展开更多
African Lions.By GIGI ROMANO.Independently Published.In the book,Gigi Romano delivers an electrifying and deeply insightful chronicle of football’s evolution across Africa.Tracing its roots from the colonial era to t...African Lions.By GIGI ROMANO.Independently Published.In the book,Gigi Romano delivers an electrifying and deeply insightful chronicle of football’s evolution across Africa.Tracing its roots from the colonial era to the present day,this captivating narrative reveals how football transformed from a pastime introduced by foreign powers into a deeply embedded cultural force and source of immense national pride.展开更多
My creative focus and interest has always been the state of human existence.Compared with grand narratives,it is often the most inadvertent,subtle actions that become my entry point.I starl a dialogue with myself by c...My creative focus and interest has always been the state of human existence.Compared with grand narratives,it is often the most inadvertent,subtle actions that become my entry point.I starl a dialogue with myself by carefully observing and deeply analyzing those subtle yet tense behaviors.Through this process,I discover and develop my own creative system to affirm the value of my existence in my work.展开更多
The seven long tunnels of Jinping II hydropower station are deeply buried.The width and evolution characteristics of excavation damaged zone(EDZ) are the key problem to the design of tunnels excavation and supports.In...The seven long tunnels of Jinping II hydropower station are deeply buried.The width and evolution characteristics of excavation damaged zone(EDZ) are the key problem to the design of tunnels excavation and supports.In order to study this problem,several specific experimental tunnels with different overburden and geometric sizes were excavated at this site.Digital borehole camera,sliding micrometer,cross-hole acoustic wave equipment and acoustic emission apparatus were adopted.This paper introduced the comprehensive in situ experimental methods through pre-installed facilities and pre-drilled boreholes.Typical properties of the surrounding rock mass,including cracks,deformation,elastic wave and micro fractures,were measured during the whole process of the tunnel excavation.The width and characteristics of formation and evolution of tunnels EDZ were analyzed under different construction methods involving of TBM and drilling and blasting,the test tunnels were excavated by full-face or two benches.The relationships between EDZ and tunnel geometry sizes,overburden and excavation method were described as well.The results will not only contribute a great deal to the analysis of rock mass behavior in deeply buried rock mass,but also provide direct data for support design and rockburst prediction.展开更多
Using a new phenomenological KN interaction which reproduces Λ(1405) as an I = 0 bound state of KN, we have investigated K--3 He(T=0) and K--4 He(T=1/2) within the framework of the Brueckner-Hartree-Fock(BHF) theory....Using a new phenomenological KN interaction which reproduces Λ(1405) as an I = 0 bound state of KN, we have investigated K--3 He(T=0) and K--4 He(T=1/2) within the framework of the Brueckner-Hartree-Fock(BHF) theory. Our calculations show that the above kaonic nuclear systems are both deeply bound. The binding energy BK-is 124.4 MeV(94.1 MeV) and the width Γ is 11.8 MeV(25.8 MeV) for K--3He(T=0)(K--4He(T =1/2)).展开更多
In deeply buried tunneling projects,geological conditions are often complex and varied.Microseismic monitoring systems are extensively deployed to enhance construction safety.However,when the current geological condit...In deeply buried tunneling projects,geological conditions are often complex and varied.Microseismic monitoring systems are extensively deployed to enhance construction safety.However,when the current geological conditions differ from those present during the signal collection for model training,recognition accuracy tends to decline significantly.Therefore,improving the applicability and stability of microseismic waveform recognition models across varying geological conditions has emerged as a critical challenge.To address this issue,we first analyze the impact of lithological changes and the development of structural planes on the features of microseismic waveforms.Subsequently,we propose a category-domain-aligned transfer learning method that enables the transfer of recognition capabilities across geological conditions by facilitating similar feature extraction and the recognition of cross-geological fracture waveforms.In this model,feature separation modeling enhances the extraction of category features of waveforms under different geological conditions.A deep transfer learning mechanism distinguishes between unique and common features,allowing for the capture of essential features necessary for model parameter updates.Through comparative experiments and feature distribution alignment and visualization,we demonstrate that the accuracy of microseismic waveform recognition across geological conditions achieves 90%.Additionally,the performance of our method is validated using microseismic signals collected from different sections of the construction site.展开更多
主题语境:节日庆祝篇幅:352词建议用时:7分钟1 Festivals are a vital part of human culture and serve multiple purposes in society.We celebrate festivals for vari⁃ous reasons that are deeply rooted in our history,beliefs a...主题语境:节日庆祝篇幅:352词建议用时:7分钟1 Festivals are a vital part of human culture and serve multiple purposes in society.We celebrate festivals for vari⁃ous reasons that are deeply rooted in our history,beliefs and social structures.展开更多
When you are old is one of the most famous love poetry written by Irish Poet, William Butler Yeats. The paper elaborates deeply on one of the early love poetry of William Butler Yeats: When you are old. It gives an in...When you are old is one of the most famous love poetry written by Irish Poet, William Butler Yeats. The paper elaborates deeply on one of the early love poetry of William Butler Yeats: When you are old. It gives an introduction of W.B. Yeats and then discusses Yeats' s early love poetry and his muse as well as her influence in the love poetry; Then the poem When you are old is analyzed and in the meantime the original French version and the Chinese version were provided for readers' literary appreciation.展开更多
Ⅰ.文学常识1. psychological realism-It is the realistic writing that probes deeply into the complexities of characters’ thoughts and motivations.2. theme-It is the central, unifying point or idea that is made concret...Ⅰ.文学常识1. psychological realism-It is the realistic writing that probes deeply into the complexities of characters’ thoughts and motivations.2. theme-It is the central, unifying point or idea that is made concrete, developed, and explored in the ACTION and the IMATERY of a work of diction.3.climax-It is the turning point or point of highest interest in a narrative, the point at which the展开更多
基金supported by the project Major Scientific and Technological Special Project of Guizhou Province([2024]014).
文摘The load profile is a key characteristic of the power grid and lies at the basis for the power flow control and generation scheduling.However,due to the wide adoption of internet-of-things(IoT)-based metering infrastructure,the cyber vulnerability of load meters has attracted the adversary’s great attention.In this paper,we investigate the vulnerability of manipulating the nodal prices by injecting false load data into the meter measurements.By taking advantage of the changing properties of real-world load profile,we propose a deeply hidden load data attack(i.e.,DH-LDA)that can evade bad data detection,clustering-based detection,and price anomaly detection.The main contributions of this work are as follows:(i)We design a stealthy attack framework that exploits historical load patterns to generate load data with minimal statistical deviation from normalmeasurements,thereby maximizing concealment;(ii)We identify the optimal time window for data injection to ensure that the altered nodal prices follow natural fluctuations,enhancing the undetectability of the attack in real-time market operations;(iii)We develop a resilience evaluation metric and formulate an optimization-based approach to quantify the electricity market’s robustness against DH-LDAs.Our experiments show that the adversary can gain profits from the electricity market while remaining undetected.
基金financially supported by the State Key Laboratory of Geohazard Prevention and Geoenvironment Protection(Chengdu University of Technology)(Grant No.SKLGP2020Z007)。
文摘Deeply buried mountain tunnels are often exposed to the risk of rock bursts,which always cause serious damage to the supporting structures and threaten the safety of the engineers.Due to the limited data available,a suitable approach to predict the rockburst tendency at the preliminary stage becomes very important.In this study,an integrated methodology combining 3D initial stress inversion and rockburst tendency prediction was developed and subsequently applied to a case study of the Sangzhuling Tunnel on the Sichuan–Tibet Railway.The numerical modelling involved inverting the initial stress field using a multiple linear regression method.The tunnel excavation was simulated separately by FDM and DEM,based on a stress boundary condition from the inverted stress field.The comparative analysis demonstrates that the rockburst ratio calculated using DEM(76.70%)exhibits a slight increase compared to FDM(75.38%),and the rockburst location is consistent with the actual situation.This suggests that DEM is more suitable for simulating the stress redistribution during excavation in a jointed rock mass.The numerical simulation combined with the deviatoric stress approach effectively predicts rockburst tendency,meeting the engineering requirements.Despite its limitations,numerical simulation remains a reliable method for predicting rock bursts.
基金funded by the National Science Foundation of China(Grant Nos.41702374,4177020938,2018YFC1505406)China Geological Survey projects(Grant Nos.DD20190640,20190505)
文摘Rock–soil aggregate landslides(RSALs) are a common geological hazard in deeply incised valleys in southwestern China. Large-scale RSALs are widely distributed in the upper reaches of the Dadu River, Danba County, Sichuan Province, and are influenced by slope structure, which can be divided into open, lock, strip, and dumbbell types, as well as soil type and meso-structure, which can be classified as layered rock–soil aggregate, block-soil, and grainsoil. In this study, the evolution of four types of structures, such as layered-dumbbell, block-soil lock, banded block-soil, and block-soil open types, were analyzed by field surveys, surface and deep displacement monitoring, and Flac3 D. It was found that the Danba reach of the Dadu River showed incised valley through the evolution from wide to slow valley affected by internal and external geological processes since the Quaternary Glaciation. In the layered-dumbbell rock–soil aggregate, the main sliding pattern is multi-stage sliding at different depths. Circular sliding in the trailing edge and plane sliding along the bedrock in the front edge body occurin the block-soil-lock type aggregate. Large-scale multi-level and circular sliding over long distances occur in the banded block-soil aggregate. The blocksoil open type is stable, with only circular sliding occurring in local and shallow surfaces of the body. The monitoring and numerical simulation results further show that slope structure and regularity have diversified with RSALs. The results provide a basis for analyzing the stability mechanism of RSALs and preventing RSALs in deeply incised valleys.
文摘The response of dynamic wave pressures on structures would be more complicated and bring about new phenomena under the dynamic interaction between soil and structure. In order to better understand the response characteristics on deeply embedded large cylindrical structures under random waves, and accordingly to offer valuable findings for engineering, the authors designed wave flume experiments to investigate comparatively dynamic wave pressures on a single and on continuous cylinders with two different embedment depths in response to two wave spectra.The time histories of the water surface elevation and the corresponding dynamic wave pressures exerted on the cylinder were analyzed in the frequency domain. By calculating the transfer function and spectral density for dynamic wave pressures along the height and around the circumference of the cylinder, experimental results of the single cylinder were compared with the theoretical results based on the linear diffraction theory, and detailed comparisons were also carried out between the single and continuous cylinders. Some new findings and the corresponding analysis are reported in present paper. The investigation on continuous cylinders will be used in particular for reference in engineering applications because information is scarce on studying such kind of problem both analytically and experimentally.
基金Projects(51374257,50804060)supported by the National Natural Science Foundation of ChinaProject(NCET-09-0844)supported by the New Century Excellent Talent Foundation from MOE of China
文摘Due to the extreme complexity of mechanical response of soft surrounding rock(SR) around a tunnel under high geostatic stress conditions, the integration of physical and numerical modeling techniques was adopted. Based on the similarity theory, new composite-similar material was developed, which showed good agreement with the similarity relation and successfully simulated physico-mechanical properties(PMP) of deep buried soft rock. And the 800 mm×800 mm×200 mm physical model(PM) was conducted, in which the endoscopic camera technique was adopted to track the entire process of failure of the model all the time. The experimental results indicate that the deformation of SR around a underground cavern possessed the characteristics of development by stages and in delay, and the initial damage of SR could induce rapid failure in the later stage, and the whole process could be divided into three stages, including the localized extension of crack(the horizontal load(HL) was in the range of 130 k N to 170 k N, the vertical load(VL) was in the range of 119 k N to 153.8 k N), rapid crack coalescence(the HL was in the range of 170 k N to 210 k N, the VL was in the range of 153.8 k N to 182.5 k N) and residual strength(the HL was greater than 210 k N, the VL was greater than 182.5 k N). Under the high stress conditions, the phenomenon of deformation localization in the SR became serious and different space positions show different deformation characteristics. In order to further explore the deformation localization and progressive failure phenomenon of soft SR around the deeply buried tunnel, applying the analysis software of FLAC3 D three-dimensional explicit finite-difference method, based on the composite strain-softening model of Mohr-Coulomb shear failure and tensile failure, the calculation method of large deformation was adopted. Then, the comparative analysis between the PM experiment and numerical simulation of the three centered arch tunnels was implemented and the relationship of deformation localization and progressive failure of SR around a tunnel under high stress conditions was discussed.
基金provided by the Natural Science Foundation of Jiangsu Province(No.BK20141130)the Fundamental Research Funds for the Central Universities(Nos.2014QNB27 and 2010QNB22)
文摘Based on the characteristics of surrounding rocks for deeply inclined roadway affected by argillation and water seepage, a structure model of layer crack plate was established to analyze the shear sliding instability mechanism. Through solid mechanics analysis of anchored surrounding rock with defect from water seepage, combined with numerical analysis for instability mechanism under water seepage in deeply inclined roadway, key factors were proposed. Results show that with increasing height of layer crack plate, lateral buckling critical load value for high wall of the roadway decreases; there is a multistage distribution for tensile stress along the anchor bolt with defect under pulling state condition;groundwater seepage seriously affects the strength of surrounding rock of the roadway, to some extent the plastic zone of the high side rises up to 8 m. Finally some support strategies were proposed for the inclined roadway and successfully applied to Haoyuan coal mine in Tiela mining area,western China.
文摘许多字典和书籍都把be deeply in debt译成"债台高筑",一直以来,这已成为一个约定俗成的译法。然而,从隐喻特别是容器隐喻的角度看,英文与中文是两种完全不同的意象:be deeply in debt是陷入其中,而"债台高筑"则是凸起于地面上。本文通过分析be-in-something关系的容器隐喻及其已有的对应翻译,力求找到be deeply in debt的新译文。
基金supported by SinoProbe (Grant 08-01)the National Natural Science Foundation of China (Grant Nos.41174035 and 41130316)+1 种基金the National High Technology Research and Development Program of China (863 Program) (Grant No.2009AA093401-05)the Major State Basic Research Development Program of China (973 Program) (Grant No.2012CB417301)
文摘Recent high-resolution deep seismic reflection profile across the Kunlun fault in northeastern Tibet shows clearly that the Moho is cut off by a complex thrust fault system. Moho offset is a general phenomenon, but little is known about the dynamic mechanism. In this study, contact models with Maxwell materials are used to simulate the mechanical process of Moho offset induced by the aseismic slip of deeply buried faults. Based on the seismic reflection data, we project a single fault model and a complex fault system model with two faults inter- secting. The deformations of the Moho, the aseismic slips, and contact stresses on faults in different models are discussed in detail. Results show that the Moho offset might be produced by aseismic slip of deeply buried faults, and the magnitude is influenced by the friction coefficient of faults and the viscosity of the lower crust. The maximum slip occurs near the Moho on the single fault or at the crossing point of two intersecting faults system. Stress concentrates mainly on the Moho, the deep end of faults, or the crossing point. This study will throw light on understanding the mechanism of Moho offset and aseismic slip of deeply buried faults. The results of complex fault system with two faults intersecting are also useful to understand the shallow intersecting faults that may cause earthquakes.
基金funded by the Natural Science Foundation of China Project(Grant Nos.41821002,41872140)the Special fund for Taishan Scholar Project(Grant No.tsqn201909061)the Fundamental Research Funds for the Central Universities(Grant No.20CX06067A)。
文摘Organic-inorganic interactions between hydrocarbons and most minerals in deeply buried reservoirs remain unclear.In this study,gold capsules and fused silica capillary capsules(FSCCs)with different com-binations of nC_(16)H_(34),water(distilled water,CaCl_(2) water)and minerals(quartz,feldspar,calcite,kaolinite,smectite,and illite)were heated at 340℃ for 3-10 d,to investigate the evolution and reaction pathways of the organic-inorganic interactions in different hot systems.After heating,minerals exhibited little alteration in the anhydrous systems.Mineral alterations,how-ever,occurred obviously in the hydrous systems.Different inorganic components affected nC_(16)H_(34) degra-dation differently.Overall,water promoted the free-radical thermal-cracking reaction and step oxidation reaction but suppressed the free-radical cross-linking reaction.The impact of CaCl_(2) water on the nC_(16)H_(34) degradation was weaker than the distilled water as high Ca^(2+)concentration suppressed the formation of free radicals.The presence of different waters also affects the impact of different minerals on nC_(16)H_(34) degradation,via its impact on mineral alterations.In the anhydrous nC_(16)H_(34)-mineral systems,calcite and clays catalyzed generation of low-molecular-weight(LMW)alkanes,particularly the clays.Quartz,feldspar,and calcite catalyzed generation of high-molecular-weight(HMW)alkanes and PAHs,whereas clays catalyzed the generation of LMW alkanes and mono-bicyclic aromatic hydrocarbons(M-BAHs).In the hydrous nC_(16)H_(34)-distilled water-mineral systems,all minerals but quartz promoted nC_(16)H_(34) degra-dation to generate more LMW alkanes,less HMW alkanes and PAHs.In the nC_(16)H_(34)-CaCl_(2) water-mineral systems,the promotion impact of minerals was weaker than that in the systems with distilled water.This study demonstrated the generation of different hydrocarbons with different fluorescence colors in the different nC_(16)H_(34)-water-mineral systems after heating for the same time,implying that fluorescence colors need to be interpreted carefully in investigation of hydrocarbon charging histories and oil origins in deeply buried reservoirs.Besides,the organic-inorganic interactions in different nC_(16)H_(34)-water-mineral systems proceeded in different pathways at different rates,which likely led to preservation of liquid hydrocarbons at different depth(temperature).Thus,quantitative investigations of the reaction kinetics in different hydrocarbon-water-rock systems are required to improve the prediction of hydrocar-bon evolution in deeply buried hydrocarbon reservoirs.
文摘有一种思念可以很长,有一种记忆可以很久,有一双手始终舒适,有一种情永远延续……It is a peaceful night again,everything is quiet.The moonlight shines brightly,which looks like pour-ing water and the cool wind flows through the window,
文摘African Lions.By GIGI ROMANO.Independently Published.In the book,Gigi Romano delivers an electrifying and deeply insightful chronicle of football’s evolution across Africa.Tracing its roots from the colonial era to the present day,this captivating narrative reveals how football transformed from a pastime introduced by foreign powers into a deeply embedded cultural force and source of immense national pride.
文摘My creative focus and interest has always been the state of human existence.Compared with grand narratives,it is often the most inadvertent,subtle actions that become my entry point.I starl a dialogue with myself by carefully observing and deeply analyzing those subtle yet tense behaviors.Through this process,I discover and develop my own creative system to affirm the value of my existence in my work.
基金supported by the National Basic Research Program of China("973"Program)(Grant No.2010CB732006)the National Natural Science Foundation of China(Grant No.40902091)supported by the CAS/SAFEA International Partnership Program for Creative Research Teams
文摘The seven long tunnels of Jinping II hydropower station are deeply buried.The width and evolution characteristics of excavation damaged zone(EDZ) are the key problem to the design of tunnels excavation and supports.In order to study this problem,several specific experimental tunnels with different overburden and geometric sizes were excavated at this site.Digital borehole camera,sliding micrometer,cross-hole acoustic wave equipment and acoustic emission apparatus were adopted.This paper introduced the comprehensive in situ experimental methods through pre-installed facilities and pre-drilled boreholes.Typical properties of the surrounding rock mass,including cracks,deformation,elastic wave and micro fractures,were measured during the whole process of the tunnel excavation.The width and characteristics of formation and evolution of tunnels EDZ were analyzed under different construction methods involving of TBM and drilling and blasting,the test tunnels were excavated by full-face or two benches.The relationships between EDZ and tunnel geometry sizes,overburden and excavation method were described as well.The results will not only contribute a great deal to the analysis of rock mass behavior in deeply buried rock mass,but also provide direct data for support design and rockburst prediction.
基金Supported by National Nature Science Foundation of China (10775059)
文摘Using a new phenomenological KN interaction which reproduces Λ(1405) as an I = 0 bound state of KN, we have investigated K--3 He(T=0) and K--4 He(T=1/2) within the framework of the Brueckner-Hartree-Fock(BHF) theory. Our calculations show that the above kaonic nuclear systems are both deeply bound. The binding energy BK-is 124.4 MeV(94.1 MeV) and the width Γ is 11.8 MeV(25.8 MeV) for K--3He(T=0)(K--4He(T =1/2)).
基金supported by the National Natural Science Foundation of China(Grant Nos.U23A20297,52222810,52309126 and 52109116).
文摘In deeply buried tunneling projects,geological conditions are often complex and varied.Microseismic monitoring systems are extensively deployed to enhance construction safety.However,when the current geological conditions differ from those present during the signal collection for model training,recognition accuracy tends to decline significantly.Therefore,improving the applicability and stability of microseismic waveform recognition models across varying geological conditions has emerged as a critical challenge.To address this issue,we first analyze the impact of lithological changes and the development of structural planes on the features of microseismic waveforms.Subsequently,we propose a category-domain-aligned transfer learning method that enables the transfer of recognition capabilities across geological conditions by facilitating similar feature extraction and the recognition of cross-geological fracture waveforms.In this model,feature separation modeling enhances the extraction of category features of waveforms under different geological conditions.A deep transfer learning mechanism distinguishes between unique and common features,allowing for the capture of essential features necessary for model parameter updates.Through comparative experiments and feature distribution alignment and visualization,we demonstrate that the accuracy of microseismic waveform recognition across geological conditions achieves 90%.Additionally,the performance of our method is validated using microseismic signals collected from different sections of the construction site.
文摘主题语境:节日庆祝篇幅:352词建议用时:7分钟1 Festivals are a vital part of human culture and serve multiple purposes in society.We celebrate festivals for vari⁃ous reasons that are deeply rooted in our history,beliefs and social structures.
文摘When you are old is one of the most famous love poetry written by Irish Poet, William Butler Yeats. The paper elaborates deeply on one of the early love poetry of William Butler Yeats: When you are old. It gives an introduction of W.B. Yeats and then discusses Yeats' s early love poetry and his muse as well as her influence in the love poetry; Then the poem When you are old is analyzed and in the meantime the original French version and the Chinese version were provided for readers' literary appreciation.
文摘Ⅰ.文学常识1. psychological realism-It is the realistic writing that probes deeply into the complexities of characters’ thoughts and motivations.2. theme-It is the central, unifying point or idea that is made concrete, developed, and explored in the ACTION and the IMATERY of a work of diction.3.climax-It is the turning point or point of highest interest in a narrative, the point at which the
