Wellbore breakout is one of the critical issues in drilling due to the fact that the related problems result in additional costs and impact the drilling scheme severely.However,the majority of such wellbore breakout a...Wellbore breakout is one of the critical issues in drilling due to the fact that the related problems result in additional costs and impact the drilling scheme severely.However,the majority of such wellbore breakout analyses were based on continuum mechanics.In addition to failure in intact rocks,wellbore breakouts can also be initiated along natural discontinuities,e.g.weak planes and fractures.Furthermore,the conventional models in wellbore breakouts with uniform distribution fractures could not reflect the real drilling situation.This paper presents a fully coupled hydro-mechanical model of the SB-X well in the Tarim Basin,China for evaluating wellbore breakouts in heavily fractured rocks under anisotropic stress states using the distinct element method(DEM)and the discrete fracture network(DFN).The developed model was validated against caliper log measurement,and its stability study was carried out by stress and displacement analyses.A parametric study was performed to investigate the effects of the characteristics of fracture distribution(orientation and length)on borehole stability by sensitivity studies.Simulation results demonstrate that the increase of the standard deviation of orientation when the fracture direction aligns parallel or perpendicular to the principal stress direction aggravates borehole instability.Moreover,an elevation in the average fracture length causes the borehole failure to change from the direction of the minimum in-situ horizontal principal stress(i.e.the direction of wellbore breakouts)towards alternative directions,ultimately leading to the whole wellbore failure.These findings provide theoretical insights for predicting wellbore breakouts in heavily fractured rocks.展开更多
This paper examines the phonemes of Chinese and Italian,conducting a statistical analysis and comparing their distinctive feature oppositions to identify challenges in phonetic learning,thereby offering suggestions fo...This paper examines the phonemes of Chinese and Italian,conducting a statistical analysis and comparing their distinctive feature oppositions to identify challenges in phonetic learning,thereby offering suggestions for teaching Chinese and Italian pronunciation.The study is divided into four parts:the first introduces the phonological definition of phonemes and delineates their scope in this context;the second compares the vowel and consonant systems of both languages,presenting foundational data on their similarities;the third analyzes the phonemic oppositions unique to each language,highlighting key differences;and the fourth proposes methods and recommendations for mastering the phonetic systems of both languages based on these differences.展开更多
Adolescence is a crucial period marked by significant developmental changes,during which risk-taking behaviors can be both a normative part of development and a potential source of concern.However,prior research has f...Adolescence is a crucial period marked by significant developmental changes,during which risk-taking behaviors can be both a normative part of development and a potential source of concern.However,prior research has focused predominantly on the adverse aspects of risk-taking(i.e.,negative risk-taking),overlooked the positive counterpart(i.e.,positive risk-taking),and lacked a detailed examination of both.This study aims to elucidate the distinct characteristics and interrelationships of positive and negative risk-taking behaviors among adoles-cents and to identify the key factors that influence these behaviors.Through a comprehensive synthesis of theoretical and empirical literature,we explore the multifaceted nature of risk-taking,highlighting its complex influencing factors,including individual traits,family dynamics,peer influence,school environment,and broader community contexts.By identifying the shared and unique factors contributing to positive and negative risk-taking behaviors,we can enable adolescents to navigate this complex stage of life and design targeted interventions.Future research directions include the application of person-centered approaches,the implementation of longitudinal tracking and the interactive effects of influencing factors,among other aspects.展开更多
Addressing the existing gap in ethical research surrounding distinct technical characteristics of Robotic Process Automation enhanced with Artificial Intelligence (AI-RPA), this analysis examines the unique ethical di...Addressing the existing gap in ethical research surrounding distinct technical characteristics of Robotic Process Automation enhanced with Artificial Intelligence (AI-RPA), this analysis examines the unique ethical dimensions by positioning AI-RPA as a distinct technological subdivision. From an analytical perspective, this study highlights key characteristics such as minimal reliance on programming, rapid development cycles, and restricted algorithmic control, which differentiate AI-RPA from traditional AI systems. These characteristics underscore the need for tailored ethical considerations, to identify ethical perils within AI-RPA’s technological origins. By positioning AI-RPA as a distinct subdivision and examining its unique characteristics alongside their emerging ethical challenges, this paper enriches the evolving discourse on AI ethics, providing valuable insights for researchers, policymakers, and organizations implementing AI-RPA technologies.展开更多
Life-history traits represent evolutionary adaptations that mediate responses to external environments.Analyzing variation in these traits provides valuable insights into macroecological processes and supports the dev...Life-history traits represent evolutionary adaptations that mediate responses to external environments.Analyzing variation in these traits provides valuable insights into macroecological processes and supports the development of effective conservation and restoration strategies.However,large-scale biogeographic patterns in life-history trait diversity among terrestrial vertebrates remain insufficiently characterized,and the processes shaping these patterns are not well understood.This study integrated life-history and spatial distribution data for 2334 terrestrial vertebrate species in China,including 398 amphibians,211 reptiles,541 mammals,and 1184 birds,to evaluate spatial patterns of trait diversity and identify underlying drivers.Assemblages in South and Southwest China exhibited high species richness,substantial assemblage-level evolutionary distinctiveness,expanded trait volumes,and elevated trait densities compared to null expectations,indicating roles as both evolutionary museums and cradles.In contrast,assemblages on the Tibetan Plateau showed expanded trait volumes but low trait densities,reflecting niche expansion among limited taxa.These findings emphasize the importance of niche packing before assemblages reach environmental carrying limits.Assemblages with high evolutionary distinctiveness tended to display high trait volumes and low trait densities,suggesting a consistent relationship between phylogenetic structure and functional diversification.Among the four groups,amphibians showed the highest sensitivity to environmental variation,highlighting the need for focused conservation efforts.Overall,this study revealed pronounced spatial heterogeneity in trait diversity across China,shaped by species richness,evolutionary distinctiveness,and environmental variation,providing valuable insights for refining conservation priorities for terrestrial vertebrate taxa.展开更多
The cubic pyrochlore Tl_(2)Ru_(2)O_(7) undergoes concurrently a metal–insulator transition (MIT) and a first-order structural transition at T_(MIT)≈120 K,below which the system was found to form one-dimensional spin...The cubic pyrochlore Tl_(2)Ru_(2)O_(7) undergoes concurrently a metal–insulator transition (MIT) and a first-order structural transition at T_(MIT)≈120 K,below which the system was found to form one-dimensional spin-one Haldane chains associated with an orbital ordering of Ru-4d electrons.With an aim to tune and access distinct ground states with strong entanglements of multiple degrees of freedom,i.e.,spin,orbital,charge,and lattice,we utilize a high-pressure approach to regulate the MIT of this system.Our detailed resistivityρ(T) measurements on the polycrystalline Tl_(2)Ru_(2)O_(7) samples under various hydrostatic pressures indeed reveal an unusual evolution of the electronic ground states.At first,the MIT is suppressed monotonically from 120 K at ambient to about 70 K at 1.5 GPa and then vanishes suddenly at about 1.8 GPa without achieving a metallic ground state.Meanwhile,the system evolves into a semiconducting ground state with magnitude ofρ(T) in the entire temperature range enhanced gradually by further increasing pressure.Prior to the abrupt disappearance of MIT,a new electronic order manifested as a kink-like anomaly inρ(T) emerges at T_(0)>T_(MIT) at 1.2 GPa and it continues to increase with pressure,producing a tricritical-point-like behavior in the T–P phase diagram of Tl_(2)Ru_(2)O_(7).The presence of two successive transitions at T_(0 )and T_(MIT )in the pressure range 1.2–1.5 GPa indicates an inhomogeneous electronic state nearby the tricritical point.At P≥3 GPa,another broad anomaly emerges inρ(T) at T_(1)>T_(0),and T_(1)continuously increases with pressure,dividing the semiconductingρ(T) into distinct thermally activated regions.These rich phenomena in the pressurized Tl_(2)Ru_(2)O_(7) should originate from the complex interplay of strongly entangled multiple quantum degrees of freedom in the system near the localized-to-itinerant crossover regime.展开更多
Despite the prevalence and validity of the universal distinct element code(UDEC)in simulations in geotechnics domain,water-weakening process of rock models remains elusive.Prior research has made positive contribution...Despite the prevalence and validity of the universal distinct element code(UDEC)in simulations in geotechnics domain,water-weakening process of rock models remains elusive.Prior research has made positive contributions to a presupposed link between modelling parameters and saturation degree,Sr.Nevertheless,this effort presents inaccurate results and limited implications owing to the misleading interpretation,that is,devoid of the basic logic in UDEC that modelling parameters should be calibrated by tested macroscopic properties in contrast to a presupposed relation with Sr.To fill this gap,a new methodology is proposed by coupling a computationally efficient parametric study with the simulation of water-weakening mechanisms.More specifically,tested macroscopic properties with different Sr values are input into parametric relations to acquire initial modelling parameters that are sequentially calibrated and modulated until simulations are in line with geomechanical tests.Illustrative example reveals that numerical water-weakening effects on macroscopic properties,mechanical behaviours,and failure configurations are highly consistent with tested ones with noticeable computational expediency,implying the feasibility and simplicity of this methodology.Furthermore,with compatibility across various numerical models,the proposed methodology substantially extends the applicability of UDEC in simulating water-weakening geotechnical problems.展开更多
Detecting the complexity of natural systems,such as hydrological systems,can help improve our understanding of complex interactions and feedback between variables in these systems.The correlation dimension method,as o...Detecting the complexity of natural systems,such as hydrological systems,can help improve our understanding of complex interactions and feedback between variables in these systems.The correlation dimension method,as one of the most useful methods,has been applied in many studies to investigate the chaos and detect the intrinsic dimensions of underlying dynamic systems.However,this method often relies on manual inspection due to uncertainties from iden-tifying the scaling region,making the correlation dimension value calculation troublesome and subjective.Therefore,it is necessary to propose a fast and intelligent algorithm to solve the above problem.This study implies the distinct windows tracking technique and fuzzy C-means clustering algorithm to accu-rately identify the scaling range and estimate the correlation dimension values.The proposed method is verified using the classic Lorenz chaotic system and 10 streamflow series in the Daling River basin of Liaoning Province,China.The results reveal that the proposed method is an intelligent and robust method for rapidly and accurately calculating the correlation dimension values,and the average operation efficiency of the proposed algorithm is 30 times faster than that of the original Grassberger-Procaccia algorithm.展开更多
Editor’s Note:On the northeastern edge of the Qinghai-Xizang Plateau,Qinghai weaves a dynamic ecological symphony composed of four distinct natural languages.Here,one can find not only solidified waves-represented by...Editor’s Note:On the northeastern edge of the Qinghai-Xizang Plateau,Qinghai weaves a dynamic ecological symphony composed of four distinct natural languages.Here,one can find not only solidified waves-represented by the crystal-clear Qarhan Salt Lake-but also flowing flames-the passionate hues of the Guide Danxia landscape.展开更多
Abundant genetic diversity and rational population structure of germplasm benefit crop breeding greatly.To investigate genetic variation among geographically diverse set of japonica germplasm,we analyzed 233 japonica ...Abundant genetic diversity and rational population structure of germplasm benefit crop breeding greatly.To investigate genetic variation among geographically diverse set of japonica germplasm,we analyzed 233 japonica rice cultivars collected from Liaoning,Jilin and Heilongjiang provinces of China,which were released from 1970 to 2011 by using 62 simple sequence repeat（SSR） markers and 8 functional gene tags related to yield.A total of 195 alleles（N_a） were detected with an average of 3.61 per locus,indicating a low level of genetic diversity level among all individuals.The genetic diversity of the cultivars from Jilin Province was the highest among the three geographic distribution zones.Moreover,the genetic diversity was increased slightly with the released period of cultivars from 1970 to 2011.The analysis of molecular variance（AMOVA） revealed that genetic differentiation was more diverse within the populations than that among the populations.The neighbor-joining（NJ） tree indicated that cultivar clusters based on geographic distribution represented three independent groups,among which the cluster of cultivars from Heilongjiang is distinctly different to the cluster of cultivars from Liaoning.For the examined functional genes,two or three allelic variations for each were detected,except for IPA1 and GW2,and most of elite genes had been introgressed in modem japonica rice varieties.These results provide a valuable evaluation for genetic backgrounds of current japonica rice and will be used directly for japonica rice breeding in future.展开更多
By taking Bixi Town of Changshu City of Jiangsu Province in China for example,through the analysis of its development including villages types,industrial layout and existing problems,development strategies for basic f...By taking Bixi Town of Changshu City of Jiangsu Province in China for example,through the analysis of its development including villages types,industrial layout and existing problems,development strategies for basic facilities in villages of Bixi Town have been illustrated from the perspective of road system,water supply and drainage system,power supply engineer,communication facilities,cable television engineer and sanitation engineer.Strategies contain building famous historical and cultural villages,developing leisure agriculture and developing distinctive agricultural undertakings.It is expected to provide development strategies for small towns and villages under the background of new countryside construction.展开更多
It has been confirmed that climatic anomaly influenced human life and production andeven causes disasters. With the economic activity developing in the world,the influence isbecoming more and more greater.Scientists h...It has been confirmed that climatic anomaly influenced human life and production andeven causes disasters. With the economic activity developing in the world,the influence isbecoming more and more greater.Scientists have long been devoting themselves to the studyof the cause of climatic anomaly. Now they distinctly attribute the cause to the ocean,where life originated from.Numerous observatons have confirmed that El Nino,known展开更多
1.Introduction The measurements of the time delay(phase)and field strength of Loran—C100kHz sky—wave signal(transmitting station:26°36′N,128°09′E,2006kmfrom Lintong)were continuously conducted at Lintong...1.Introduction The measurements of the time delay(phase)and field strength of Loran—C100kHz sky—wave signal(transmitting station:26°36′N,128°09′E,2006kmfrom Lintong)were continuously conducted at Lintong(34°22′N,109°13′E)展开更多
By using multi-objective analysis method, five architectural tourist sites with Lingnan characteristics were selected. Through the analysis on relevant data obtained by GIS, spatial analysis research had been conducte...By using multi-objective analysis method, five architectural tourist sites with Lingnan characteristics were selected. Through the analysis on relevant data obtained by GIS, spatial analysis research had been conducted on competitiveness of Lingnan distinctive architectural tourist cultural sites in Guangdong Province and some conclusions had been obtained.展开更多
On 16 August,1989,in the space above the active region 5629(S16W96)a X20X—ray flare was produced.It lasted for 13 hours and its X—ray storm was the largest onein the solar X—ray observation record.We observed it wi...On 16 August,1989,in the space above the active region 5629(S16W96)a X20X—ray flare was produced.It lasted for 13 hours and its X—ray storm was the largest onein the solar X—ray observation record.We observed it with using the Chromospheric HαMonitor equiped in the Two—dimensional Multi—band Solar Spectrograph at展开更多
Using spontaneous parametric down conversion,polarization post selection and coincidence counting technique,the polarization Einstein-Podolsky-Rosen(EPR) entangled states are prepared.Experimental studies on the effic...Using spontaneous parametric down conversion,polarization post selection and coincidence counting technique,the polarization Einstein-Podolsky-Rosen(EPR) entangled states are prepared.Experimental studies on the efficiency,contrast and fidelity with different pump laser intensities are performed systematically.The results show that the pump laser intensity distinctly influences the quality of entangled photons,especially the contrast and the fidelity.On the other hand,the pump efficiency of entangled photons is almost invariable,namely the entangled source brightness increases linearly with the increase of pump laser power.展开更多
This article briefs the past and development of independent colleges until now in China,dealing with the reasons why they have come into existence and developed in a remarkable way.A somewhat detailed analysis of thei...This article briefs the past and development of independent colleges until now in China,dealing with the reasons why they have come into existence and developed in a remarkable way.A somewhat detailed analysis of their distinctions from other higher education has been made and the further development strategies are also presented in it.展开更多
基金supported by National Natural Science Foundation of China(Grant Nos.52074312 and 52211530097)CNPC Science and Technology Innovation Foundation(Grant No.2021DQ02-0505).
文摘Wellbore breakout is one of the critical issues in drilling due to the fact that the related problems result in additional costs and impact the drilling scheme severely.However,the majority of such wellbore breakout analyses were based on continuum mechanics.In addition to failure in intact rocks,wellbore breakouts can also be initiated along natural discontinuities,e.g.weak planes and fractures.Furthermore,the conventional models in wellbore breakouts with uniform distribution fractures could not reflect the real drilling situation.This paper presents a fully coupled hydro-mechanical model of the SB-X well in the Tarim Basin,China for evaluating wellbore breakouts in heavily fractured rocks under anisotropic stress states using the distinct element method(DEM)and the discrete fracture network(DFN).The developed model was validated against caliper log measurement,and its stability study was carried out by stress and displacement analyses.A parametric study was performed to investigate the effects of the characteristics of fracture distribution(orientation and length)on borehole stability by sensitivity studies.Simulation results demonstrate that the increase of the standard deviation of orientation when the fracture direction aligns parallel or perpendicular to the principal stress direction aggravates borehole instability.Moreover,an elevation in the average fracture length causes the borehole failure to change from the direction of the minimum in-situ horizontal principal stress(i.e.the direction of wellbore breakouts)towards alternative directions,ultimately leading to the whole wellbore failure.These findings provide theoretical insights for predicting wellbore breakouts in heavily fractured rocks.
文摘This paper examines the phonemes of Chinese and Italian,conducting a statistical analysis and comparing their distinctive feature oppositions to identify challenges in phonetic learning,thereby offering suggestions for teaching Chinese and Italian pronunciation.The study is divided into four parts:the first introduces the phonological definition of phonemes and delineates their scope in this context;the second compares the vowel and consonant systems of both languages,presenting foundational data on their similarities;the third analyzes the phonemic oppositions unique to each language,highlighting key differences;and the fourth proposes methods and recommendations for mastering the phonetic systems of both languages based on these differences.
基金Soft Science Special Project of Gansu Basic Research Plan,No.25JRZA072Youth Project of Philosophy and Social Science Foundation of Gansu Province,No.2024QN015+1 种基金General Project of Philosophy and Social Science Foundation of Gansu Province,No.2024YB049Lanzhou Philosophy and Social Science Planning Project,No.24-B13.
文摘Adolescence is a crucial period marked by significant developmental changes,during which risk-taking behaviors can be both a normative part of development and a potential source of concern.However,prior research has focused predominantly on the adverse aspects of risk-taking(i.e.,negative risk-taking),overlooked the positive counterpart(i.e.,positive risk-taking),and lacked a detailed examination of both.This study aims to elucidate the distinct characteristics and interrelationships of positive and negative risk-taking behaviors among adoles-cents and to identify the key factors that influence these behaviors.Through a comprehensive synthesis of theoretical and empirical literature,we explore the multifaceted nature of risk-taking,highlighting its complex influencing factors,including individual traits,family dynamics,peer influence,school environment,and broader community contexts.By identifying the shared and unique factors contributing to positive and negative risk-taking behaviors,we can enable adolescents to navigate this complex stage of life and design targeted interventions.Future research directions include the application of person-centered approaches,the implementation of longitudinal tracking and the interactive effects of influencing factors,among other aspects.
文摘Addressing the existing gap in ethical research surrounding distinct technical characteristics of Robotic Process Automation enhanced with Artificial Intelligence (AI-RPA), this analysis examines the unique ethical dimensions by positioning AI-RPA as a distinct technological subdivision. From an analytical perspective, this study highlights key characteristics such as minimal reliance on programming, rapid development cycles, and restricted algorithmic control, which differentiate AI-RPA from traditional AI systems. These characteristics underscore the need for tailored ethical considerations, to identify ethical perils within AI-RPA’s technological origins. By positioning AI-RPA as a distinct subdivision and examining its unique characteristics alongside their emerging ethical challenges, this paper enriches the evolving discourse on AI ethics, providing valuable insights for researchers, policymakers, and organizations implementing AI-RPA technologies.
基金supported by the National Key Program of Research and Development,Ministry of Science and Technology(2022YFF1301401,2022YFF0802300)National Natural Science Foundation of China(32370553)+3 种基金Second Tibetan Plateau Scientific Expedition and Research Program(STEP,2019QZKK0501)China Biodiversity Observation Networks(Sino BON)Fundamental Research Funds for the Central Universities(SWU-KR24004)Scientific Research Innovation Project of Graduate Student of Southwest University(SWUB23080)。
文摘Life-history traits represent evolutionary adaptations that mediate responses to external environments.Analyzing variation in these traits provides valuable insights into macroecological processes and supports the development of effective conservation and restoration strategies.However,large-scale biogeographic patterns in life-history trait diversity among terrestrial vertebrates remain insufficiently characterized,and the processes shaping these patterns are not well understood.This study integrated life-history and spatial distribution data for 2334 terrestrial vertebrate species in China,including 398 amphibians,211 reptiles,541 mammals,and 1184 birds,to evaluate spatial patterns of trait diversity and identify underlying drivers.Assemblages in South and Southwest China exhibited high species richness,substantial assemblage-level evolutionary distinctiveness,expanded trait volumes,and elevated trait densities compared to null expectations,indicating roles as both evolutionary museums and cradles.In contrast,assemblages on the Tibetan Plateau showed expanded trait volumes but low trait densities,reflecting niche expansion among limited taxa.These findings emphasize the importance of niche packing before assemblages reach environmental carrying limits.Assemblages with high evolutionary distinctiveness tended to display high trait volumes and low trait densities,suggesting a consistent relationship between phylogenetic structure and functional diversification.Among the four groups,amphibians showed the highest sensitivity to environmental variation,highlighting the need for focused conservation efforts.Overall,this study revealed pronounced spatial heterogeneity in trait diversity across China,shaped by species richness,evolutionary distinctiveness,and environmental variation,providing valuable insights for refining conservation priorities for terrestrial vertebrate taxa.
基金supported by the National Key Research and Development Program of China (Grant Nos. 2023YFA1406100 and 2021YFA1400200)the National Natural Science Foundation of China (Grant Nos. 12025408 and 12174424)+2 种基金the Youth Innovation Promotion Association of Chinese Academy of Scineces (Grant No. 2023007)support from the National Natural Science Foundation of China (Grant No. 11904272)the Open Fund of Hubei Provincial Key Laboratory of Metallurgical Industry Process Systems Science (Grant No. Z202202)。
文摘The cubic pyrochlore Tl_(2)Ru_(2)O_(7) undergoes concurrently a metal–insulator transition (MIT) and a first-order structural transition at T_(MIT)≈120 K,below which the system was found to form one-dimensional spin-one Haldane chains associated with an orbital ordering of Ru-4d electrons.With an aim to tune and access distinct ground states with strong entanglements of multiple degrees of freedom,i.e.,spin,orbital,charge,and lattice,we utilize a high-pressure approach to regulate the MIT of this system.Our detailed resistivityρ(T) measurements on the polycrystalline Tl_(2)Ru_(2)O_(7) samples under various hydrostatic pressures indeed reveal an unusual evolution of the electronic ground states.At first,the MIT is suppressed monotonically from 120 K at ambient to about 70 K at 1.5 GPa and then vanishes suddenly at about 1.8 GPa without achieving a metallic ground state.Meanwhile,the system evolves into a semiconducting ground state with magnitude ofρ(T) in the entire temperature range enhanced gradually by further increasing pressure.Prior to the abrupt disappearance of MIT,a new electronic order manifested as a kink-like anomaly inρ(T) emerges at T_(0)>T_(MIT) at 1.2 GPa and it continues to increase with pressure,producing a tricritical-point-like behavior in the T–P phase diagram of Tl_(2)Ru_(2)O_(7).The presence of two successive transitions at T_(0 )and T_(MIT )in the pressure range 1.2–1.5 GPa indicates an inhomogeneous electronic state nearby the tricritical point.At P≥3 GPa,another broad anomaly emerges inρ(T) at T_(1)>T_(0),and T_(1)continuously increases with pressure,dividing the semiconductingρ(T) into distinct thermally activated regions.These rich phenomena in the pressurized Tl_(2)Ru_(2)O_(7) should originate from the complex interplay of strongly entangled multiple quantum degrees of freedom in the system near the localized-to-itinerant crossover regime.
基金supported by the National Natural Science Foundation of China under Grant Nos.41977249 and 42090052the China Scholarship Council under file No.202204910040.
文摘Despite the prevalence and validity of the universal distinct element code(UDEC)in simulations in geotechnics domain,water-weakening process of rock models remains elusive.Prior research has made positive contributions to a presupposed link between modelling parameters and saturation degree,Sr.Nevertheless,this effort presents inaccurate results and limited implications owing to the misleading interpretation,that is,devoid of the basic logic in UDEC that modelling parameters should be calibrated by tested macroscopic properties in contrast to a presupposed relation with Sr.To fill this gap,a new methodology is proposed by coupling a computationally efficient parametric study with the simulation of water-weakening mechanisms.More specifically,tested macroscopic properties with different Sr values are input into parametric relations to acquire initial modelling parameters that are sequentially calibrated and modulated until simulations are in line with geomechanical tests.Illustrative example reveals that numerical water-weakening effects on macroscopic properties,mechanical behaviours,and failure configurations are highly consistent with tested ones with noticeable computational expediency,implying the feasibility and simplicity of this methodology.Furthermore,with compatibility across various numerical models,the proposed methodology substantially extends the applicability of UDEC in simulating water-weakening geotechnical problems.
基金IWHR Basic Scientific Research Project,Grant/Award Number:JZ110145B0072024IWHR Internationally-Oriented Talent for International Academic Leader Program,Grant/Award Number:0203982012National Natural Science Foundation of China,Grant/Award Number:51609257。
文摘Detecting the complexity of natural systems,such as hydrological systems,can help improve our understanding of complex interactions and feedback between variables in these systems.The correlation dimension method,as one of the most useful methods,has been applied in many studies to investigate the chaos and detect the intrinsic dimensions of underlying dynamic systems.However,this method often relies on manual inspection due to uncertainties from iden-tifying the scaling region,making the correlation dimension value calculation troublesome and subjective.Therefore,it is necessary to propose a fast and intelligent algorithm to solve the above problem.This study implies the distinct windows tracking technique and fuzzy C-means clustering algorithm to accu-rately identify the scaling range and estimate the correlation dimension values.The proposed method is verified using the classic Lorenz chaotic system and 10 streamflow series in the Daling River basin of Liaoning Province,China.The results reveal that the proposed method is an intelligent and robust method for rapidly and accurately calculating the correlation dimension values,and the average operation efficiency of the proposed algorithm is 30 times faster than that of the original Grassberger-Procaccia algorithm.
文摘Editor’s Note:On the northeastern edge of the Qinghai-Xizang Plateau,Qinghai weaves a dynamic ecological symphony composed of four distinct natural languages.Here,one can find not only solidified waves-represented by the crystal-clear Qarhan Salt Lake-but also flowing flames-the passionate hues of the Guide Danxia landscape.
基金supported by the National Natural Science Foundation of China(31371586)the Program for Liaoning Excellent Talents in University(LNET),China(LJQ2013075)
文摘Abundant genetic diversity and rational population structure of germplasm benefit crop breeding greatly.To investigate genetic variation among geographically diverse set of japonica germplasm,we analyzed 233 japonica rice cultivars collected from Liaoning,Jilin and Heilongjiang provinces of China,which were released from 1970 to 2011 by using 62 simple sequence repeat（SSR） markers and 8 functional gene tags related to yield.A total of 195 alleles（N_a） were detected with an average of 3.61 per locus,indicating a low level of genetic diversity level among all individuals.The genetic diversity of the cultivars from Jilin Province was the highest among the three geographic distribution zones.Moreover,the genetic diversity was increased slightly with the released period of cultivars from 1970 to 2011.The analysis of molecular variance（AMOVA） revealed that genetic differentiation was more diverse within the populations than that among the populations.The neighbor-joining（NJ） tree indicated that cultivar clusters based on geographic distribution represented three independent groups,among which the cluster of cultivars from Heilongjiang is distinctly different to the cluster of cultivars from Liaoning.For the examined functional genes,two or three allelic variations for each were detected,except for IPA1 and GW2,and most of elite genes had been introgressed in modem japonica rice varieties.These results provide a valuable evaluation for genetic backgrounds of current japonica rice and will be used directly for japonica rice breeding in future.
文摘By taking Bixi Town of Changshu City of Jiangsu Province in China for example,through the analysis of its development including villages types,industrial layout and existing problems,development strategies for basic facilities in villages of Bixi Town have been illustrated from the perspective of road system,water supply and drainage system,power supply engineer,communication facilities,cable television engineer and sanitation engineer.Strategies contain building famous historical and cultural villages,developing leisure agriculture and developing distinctive agricultural undertakings.It is expected to provide development strategies for small towns and villages under the background of new countryside construction.
文摘It has been confirmed that climatic anomaly influenced human life and production andeven causes disasters. With the economic activity developing in the world,the influence isbecoming more and more greater.Scientists have long been devoting themselves to the studyof the cause of climatic anomaly. Now they distinctly attribute the cause to the ocean,where life originated from.Numerous observatons have confirmed that El Nino,known
文摘1.Introduction The measurements of the time delay(phase)and field strength of Loran—C100kHz sky—wave signal(transmitting station:26°36′N,128°09′E,2006kmfrom Lintong)were continuously conducted at Lintong(34°22′N,109°13′E)
基金Supported by Basic Tourism which is the Elaborate Course of Guang-zhou Vocational College of Technology and BusinessSubtopic of 863Key Program (2006AA06A306 )+1 种基金Key Item of Weather Bureau of Shandong Province (2009sdqxz16)Geochemical Investigation Data-base (INFO-115-C01-SDB4-06) ~~
文摘By using multi-objective analysis method, five architectural tourist sites with Lingnan characteristics were selected. Through the analysis on relevant data obtained by GIS, spatial analysis research had been conducted on competitiveness of Lingnan distinctive architectural tourist cultural sites in Guangdong Province and some conclusions had been obtained.
文摘On 16 August,1989,in the space above the active region 5629(S16W96)a X20X—ray flare was produced.It lasted for 13 hours and its X—ray storm was the largest onein the solar X—ray observation record.We observed it with using the Chromospheric HαMonitor equiped in the Two—dimensional Multi—band Solar Spectrograph at
基金supported by the National Natural Science Foundation of China(No.11174224)the Natural Science Foundation of Shandong Province(Nos.ZR2013FM001,2013SJGZ10 and ZR2014JL029)+1 种基金the Science and Technology Development Program of Shandong Province(Nos.2011YD01049 and 2013YD01016)the Higher School Science and Technology Program of Shandong Province(Nos.J13LJ54 and J13LA52)
文摘Using spontaneous parametric down conversion,polarization post selection and coincidence counting technique,the polarization Einstein-Podolsky-Rosen(EPR) entangled states are prepared.Experimental studies on the efficiency,contrast and fidelity with different pump laser intensities are performed systematically.The results show that the pump laser intensity distinctly influences the quality of entangled photons,especially the contrast and the fidelity.On the other hand,the pump efficiency of entangled photons is almost invariable,namely the entangled source brightness increases linearly with the increase of pump laser power.
文摘This article briefs the past and development of independent colleges until now in China,dealing with the reasons why they have come into existence and developed in a remarkable way.A somewhat detailed analysis of their distinctions from other higher education has been made and the further development strategies are also presented in it.
