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Evolution based on genome structure: the “diagonal genome universe” 被引量:2
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作者 Kenji Sorimachi 《Natural Science》 2010年第10期1104-1112,共9页
The ratios of amino acid to the total amino acids and those of nucleotides to the total nucleotides in genes or genomes are suitable indexes to compare whole gene or genome characteristics based on the large number of... The ratios of amino acid to the total amino acids and those of nucleotides to the total nucleotides in genes or genomes are suitable indexes to compare whole gene or genome characteristics based on the large number of nucleotides rather than their sequences. As these ratios are strictly calculated from nucleotide sequences, the values are independent of experimental errors. In the present mini-review, the following themes are approached according to the ratios of amino acids and nucleotides to their total numbers in the genome: prebiotic evolution, the chronological precedence of protein and codon formations, genome evolution, Chargaff’s second pa- rity rule, and the origins of life. Amino acid formation might have initially occurred during pre- biotic evolution, the “amino acid world”, and amino acid polymerization might chronologically precede codon formation at the end of prebiotic evolution. All nucleotide alterations occurred synchronously over the genome during biolo- gical evolution. After establishing primitive lives, all nucleotide alterations have been governed by linear formulae in nuclear and organelle genomes consisting of the double-stranded DNA. When the four nucleotide contents against each individual nucleotide content in organelles are expressed by four linear regression lines representing the diagonal lines of a 0.5 square – the “Diagonal Genome Universe”, evolution obeys Chargaff’s second parity rule. The fact that linear regression lines intersect at a single point su- ggests that all species originated from a single life source. 展开更多
关键词 evolution (Prebiotic and Biological) GENOME Origin of Life Chargaffs Parity Rules ORGANELLE Double- and SINGLE-STRAND DNA Amino Acid NUCLEOTIDE Linear Formula
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Diagenesis-porosity evolution and“sweet spot”distribution of low permeability reservoirs:A case study from Oligocene Zhuhai Formation in Wenchang A sag,Pear River Mouth Basin,northern South China Sea 被引量:2
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作者 YOU Li XU Shouli +3 位作者 LI Cai ZHANG Yingzhao ZHAO Zhanjie ZHU Peiyuan 《Petroleum Exploration and Development》 2018年第2期251-263,共13页
The characteristics of low permeability reservoirs and distribution of sweet spots in the Oligocene Zhuhai Formation of Wenchang A sag, Pearl River Basin were investigated by core observation and thin section analysis... The characteristics of low permeability reservoirs and distribution of sweet spots in the Oligocene Zhuhai Formation of Wenchang A sag, Pearl River Basin were investigated by core observation and thin section analysis. The study results show that there develop the fine, medium and coarse sandstone reservoirs of tidal flat–fan delta facies, which are of mostly low permeability and locally medium permeability. There are two kinds of pore evolution patterns: oil charging first and densification later, the reservoirs featuring this pattern are mainly in the third member of Zhuhai Formation between the south fault zone and the sixth fault zone, and the pattern of densification first and gas charging later is widespread across the study area. Strong compaction and local calcium cementation are the key factors causing low permeability of the reservoirs in the Zhuhai Formation. Thick and coarse grain sand sedimentary body is the precondition to form "sweet spot" reservoirs. Weak compaction and cementation, dissolution, early hydrocarbon filling and authigenic chlorite coating are the main factors controlling formation of "sweet spot" reservoir. It is predicted that there develop between the south fault and sixth fault zones the Class Ⅰ "sweet spot" in medium compaction zone, Class Ⅱ "sweet spot" in nearly strong compaction zone, Class Ⅲ "sweet spot" reservoir in the nearly strong to strong compaction zone with oil charging at early stage, and Class IV "sweet spot" reservoir in the strong compaction and authigenic chlorite coating protection zone in the sixth fault zone. 展开更多
关键词 low permeability reservoir pore evolution hydrocarbon charging 'sweet spot' DISTRIBUTION Zhuhai Formation OLIGOCENE Wenchang A SAG northern South China Sea
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"universe collapse model"and its roles in the unification of four fundamental forces and the origin and the evolution of the universe 被引量:1
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作者 Jiapei Dai 《Natural Science》 2012年第4期199-203,共5页
To unify the four known fundamental forces and provide an explanation for the origin and the evolution of the universe are two long-term goals of theoretical physics. Here a “universe collapse model” has been propos... To unify the four known fundamental forces and provide an explanation for the origin and the evolution of the universe are two long-term goals of theoretical physics. Here a “universe collapse model” has been proposed. The universe consists of Matter and No-matter. No-matter is the universal energy that constructs a consistent universe field, presenting a spiral wave motion at the speed of light at the small scale. The partial collapse of the universal energy forms the particles of the universal energy in a variety of sizes, which are called as the elementary particles. These elementary particles form atom and matter, which construct the galaxies. The collapse of the universe field induces the formation of the universe collapse potential (UCP) and universe collapse force (UCF), and the later is represented by four different aspects of the fundamental forces at the large or small scales. The mathematical equation and the derivation of UCP and UCF are described, and possible experimental tests are also suggested. Therefore, this new model may give a novel explanation for the unification of four fundamental forces and the origin and the evolution of the universe. 展开更多
关键词 UNIVERSE COLLAPSE MODEL Field Theories Beyond Standard MODEL String Field Theory Grand Unification MODEL FUNDAMENTAL FORCES Elementary Particles The ORIGIN and evolution of UNIVERSE
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Unveiling cell-type-specific mode of evolution in comparative single-cell expression data
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作者 Tian Qin Hongju Zhang Zhengting Zou 《Journal of Genetics and Genomics》 2026年第1期28-42,共15页
While methodology for determining the mode of evolution in coding sequences has been well established,evaluation of adaptation events in emerging types of phenotype data needs further development.Here,we propose an an... While methodology for determining the mode of evolution in coding sequences has been well established,evaluation of adaptation events in emerging types of phenotype data needs further development.Here,we propose an analysis framework(expression variance decomposition,EVaDe)for comparative single-cell expression data based on phenotypic evolution theory.After decomposing the gene expression variance into separate components,we use two strategies to identify genes exhibiting large between-taxon expression divergence and small within-cell-type expression noise in certain cell types,attributing this pattern to putative adaptive evolution.In a dataset of primate prefrontal cortex,we find that such humanspecific key genes enrich with neurodevelopment-related functions,while most other genes exhibit neutral evolution patterns.Specific neuron types are found to harbor more of these key genes than other cell types,thus likely to have experienced more extensive adaptation.Reassuringly,at the molecular sequence level,the key genes are significantly associated with the rapidly evolving conserved non-coding elements.An additional case analysis comparing the naked mole-rat(NMR)with the mouse suggests that innateimmunity-related genes and cell types have undergone putative expression adaptation in NMR.Overall,the EVaDe framework may effectively probe adaptive evolution mode in single-cell expression data. 展开更多
关键词 Single-cell transcriptomics Gene expression Adaptive evolution Cell type Phenotypic evolution Prefrontal cortex Naked mole-rat
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Genetic Evolution Analysis of Rabies Virus in Jiangsu Province,China
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作者 Minghui Zhang Yuanfang Qin +8 位作者 Na zhang Yuqiao Liu Jun Yang Xiaonuo Xu Pengcheng Yu Shuqing Liu Qian Liu Xiaoyan Tao Wuyang Zhu 《Biomedical and Environmental Sciences》 2026年第2期245-250,共6页
Rabies is a zoonotic disease with an estimated global mortality of 59,000 people annually and a burden of more than 3.7 million disability-adjusted life years(DALYs)that is caused by a neurotropic lyssavirus[1].Dogs a... Rabies is a zoonotic disease with an estimated global mortality of 59,000 people annually and a burden of more than 3.7 million disability-adjusted life years(DALYs)that is caused by a neurotropic lyssavirus[1].Dogs are the primary source of human rabies,as more than 95%of human cases can be traced to dogs[2,3].China faces a substantial burden of rabies,having endured three major human rabies epidemics,which occurred in the 1950s,1981,and 2007[4].Implementation of various prevention and control measures has decreased the number of human rabies cases from 3,300 in 2007 to 167 in 2024.In China. 展开更多
关键词 rabies virus Jiangsu province neurotropic lyssavirus dogs neurotropic lyssavirus prevention control measures China genetic evolution zoonotic disease
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Tracking the complete evolution of electromagnetic instability in an ultra-intense laser-driven plasma
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作者 Moniruzzaman Shaikh Amit D.Lad +4 位作者 Devshree Mandal Kamalesh Jana Deep Sarkar Amita Das G.Ravindra Kumar 《Matter and Radiation at Extremes》 2026年第2期44-50,共7页
Plasmas,the most common state of matter in the observable universe,are subject to instabilities of various types:hydrodynamic,magnetohydrodynamic,and electromagnetic.Our limited success in understanding these is due t... Plasmas,the most common state of matter in the observable universe,are subject to instabilities of various types:hydrodynamic,magnetohydrodynamic,and electromagnetic.Our limited success in understanding these is due to the lack of direct experimental information on their origins and evolution.Here,we present direct spatially resolved measurements of the femtosecond evolution of the electromagnetic beam-driven instability that arises from the interaction of forward and return currents in an ultrahigh-intensity laser-produced plasma.We track its evolution from the initial linear stage to the later nonlinear stage by measuring the spatiotemporal evolution of the giant(megagauss)magnetic field created in the interaction process.Our experimental findings and numerical simulations are the first to indicate the observed instability triggered by the emission of electromagnetic radiation,like those known in the context of gravitational interaction,where the emission of gravitational radiation drives specific negative-energy modes in rotating black holes or neutron stars. 展开更多
关键词 electromagnetic instability forward return currents femtosecond evolution PLASMA magnetic field ultra intense laser hydrodynamic instability magnetohydrodynamic instability
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Evolutionary Origin of Religions and Religious Evolution: Religious Neurosociology
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作者 Dingyu Chung 《Journal of Behavioral and Brain Science》 2018年第9期485-511,共27页
The paper proposes that the evolutionary origin of religions is based on theory of mind as the product of interdependent division of labor between the forest specialist group (women and small children) and the woodlan... The paper proposes that the evolutionary origin of religions is based on theory of mind as the product of interdependent division of labor between the forest specialist group (women and small children) and the woodland specialist group (men) in early hominins who lived in the mixed forest-woodland habitat. To complement each other’s work without interfering each other’s work, one specialist group had to recognize (imagine) that the other specialist group existed to think for themselves and to do different works. The result was theory of mind which is to recognize (imagine) that the others exist to think for themselves. (The forest-woodland groups became the hunter-gatherer groups for the Homo species in the savanna habitat.) Under existential pressure, hominins invented imaginary specialists as imaginary agents who existed to think for themselves and to do different works in imaginary division of labor to enhance survival chance. The result was religion with imaginary behaviors. Therefore, religion is defined as a set of beliefs and behaviors based on theory of mind that produces a shared imagination to enhance survival chance under existential pressure. This paper proposes that the religious evolution consists of the premodern imaginative religion for local society habitat starting from bipedalism, the modern rational imaginative religion for regional society habitat starting from the Axial Age, and the postmodern diverse rational imaginative religion for global society habitat starting from the Information Revolution. In conclusion, the religious brain is the imaginative brain, and the religious social behaviors are imaginary social behaviors. The religious evolution is the evolution of human imagination to enhance survival chance under existential pressure, such as the religious reinforcement of social bonds to enhance the survival chance of social group and the religious relief of stress and anxiety to enhance the survival chance of individuals. 展开更多
关键词 RELIGIOUS Neurosociology evolutionary Origin of RELIGIONS RELIGIOUS evolution Neuroscience Theory of Mind Mental IMMUNE System INGROUP Social RELIGION IMMUNE RELIGION Premodern RELIGION Modern RELIGION Postmodern RELIGION
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Structure design of oxide path mechanism-based electrocatalysts for enhanced oxygen evolution reaction performance
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作者 Jin Yang Shengbo Sang Meiling Wang 《Journal of Energy Chemistry》 2026年第2期464-483,I0011,共21页
The oxygen evolution reaction(OER)suffers from sluggish kinetics,necessitating efficient electrocatalysts to reduce overpotentials in water splitting.Currently recognized OER mechanisms primarily include the adsorbate... The oxygen evolution reaction(OER)suffers from sluggish kinetics,necessitating efficient electrocatalysts to reduce overpotentials in water splitting.Currently recognized OER mechanisms primarily include the adsorbate evolution mechanism(AEM),lattice oxygen mechanism(LOM),and oxide path mechanism(OPM).Compared to AEM,limited by scaling relationships,and LOM,constrained by stability issues,the OPM offers a promising alternative by enabling direct O-O bond formation via dual active sites,thus bypassing^(*)OOH intermediates and lattice O involvement and achieving a balance between activity and durability.However,activating the OPM process requires precise control over the spatial and electronic structure of active sites,making the design of OPM-based catalysts challenging.While previous reviews have focused on homo/heteronuclear diatomic perspectives of OPM-based catalysts,it is urgent to systematically summarize design strategies to provide a rational reference for their development.Herein,a review of design strategies for OPM-based OER catalysts across three scales is comprehensively presented,including in-situ engineering,doping-enabled sites reconstruction,and introducing new sites for nanoparticles,direct synthesis or post-treatments for molecular catalysts,and doping or template strategies for atom pairs or arrays.The unique advantage of atom arrays is also highlighted,and their future research directions and possible strategies are discussed.This review provides a systematic summary and forward-looking perspectives for rationally designing high-performance OPM-based OER catalysts. 展开更多
关键词 Oxygen evolution reaction Oxide path mechanism Dual sites Nanoparticle catalysts Molecular catalysts Atom arrays Design strategies
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The Newly Discovered Pathway for Oxygen Evolution Reaction: In-Situ/Operando Characterization Techniques for Catalyst Development
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作者 Rabia Khalid Muhammad Tahir +2 位作者 Muhammad Umar Pin Fang Yujing Li 《Carbon Energy》 2026年第3期12-40,共29页
Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxyge... Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxygen evolution reaction(OER)remains a significant challenge,particularly at the industrial scale.This report explores a newly discovered pathway,the oxide path mechanism(OPM) for OER-mechanism involving the oxide formation and evolution during the reaction,emphasizing its potential to overcome existing limitations.OPM enables direct O-O coupling without oxygen vacancies,offering superior stability.We detail both classical and innovative in-situ characterization techniques that are central to unraveling the OER mechanism.The advanced in-situ electrochemical techniques,such as inductively coupled plasma mass spectroscopy,X-ray photoelectron spectroscopy,and Mössbauer spectroscopy,coupled with in-situ structural analyses,provide crucial insights into the catalyst surface,the electrode-electrolyte interface and the kinetics of OER.This review provides a systematic analysis integrating classical electrochemical methods with advanced in-situ/operando techniques,specifically focusing on understanding OPM.While numerous studies have examined individual characterization methods,this study systematically integrates traditional electrochemical approaches with in-situ and operando techniques,offering critical insights into their complementary roles in elucidating reaction pathways.The integration of these methodologies provides unprecedented understanding of catalyst behavior under operational conditions,guiding the rational design of next-generation OER catalysts.Furthermore,we discuss essential standardized test toolkits and protocols,such as those for rotating disk electrode and membrane electrode assembly,which are vital for ensuring reproducibility and scalability in OER catalyst research. 展开更多
关键词 in-situ characterization techniques mechanistic understanding OER catalyst operando spectroscopy oxygen evolution reaction(OER) renewable energy water splitting
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Coupled FEM-DEM modeling of permeability evolution in rough fractured shale during shearing under varying confining pressures
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作者 Bin Li Qi Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第3期1736-1754,共19页
The dynamic evolution of fracture permeability presents a critical scientific challenge in rock masses.Understanding the mechanisms of rock mass permeability evolution is vital for engineering project design and opera... The dynamic evolution of fracture permeability presents a critical scientific challenge in rock masses.Understanding the mechanisms of rock mass permeability evolution is vital for engineering project design and operations.By integrating the discrete element method(DEM)with the finite element method(FEM),a numerical simulation framework for shear seepage in rough fractured shale has been developed to investigate the dynamic mechanisms of permeability evolution under varying confining pressures and during the shearing process.Numerical simulations were conducted on rough fractured samples under effective confining pressures ranging from 5 MPa to 20 MPa to monitor the aperture and permeability evolution of the fracture.The results of the numerical simulation are consistent with the experimental observations,indicating that both the shearing process and confining pressure significantly influence permeability.Moreover,the magnitude of the confining pressure is a crucial factor influencing the trend in permeability changes.Under a confining pressure of 5 MPa,fracture permeability initially increases significantly but decreases post-shearing.In contrast,a continuous decrease in fracture permeability is observed when the confining pressure exceeds 10 MPa.The results of the shear numerical simulation indicate that the confining pressure restricts fracture dilation during shearing,promotes the generation of rock debris,and decreases both the permeability and transmissivity of the fracture.The wear results obtained from numerical simulations are consistent with the experimental patterns and correlate with the joint roughness coefficient(JRC).This study proposed an effective numerical simulation method to reveal the evolution mechanism of fracture flow capacity,taking into account the wear of the fracture surface in shear simulations and the initial stress state of the rock in seepage simulations.This research explains the permeability evolution mechanism of fractured shale from a microscopic perspective,and the proposed numerical simulation method for shear seepage provides a powerful means to uncover the dynamic evolution mechanisms governing fracture permeability. 展开更多
关键词 Discrete element method(DEM) Finite element method(FEM) Fracture Permeability Shear stress Joint roughness coefficient(JRC) Dynamic evolution
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Analytical Treatment of the Evolutionary (1 + 1)-Dimensional Combined KdV-mKdV Equation via the Novel (G'/G)-Expansion Method 被引量:2
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作者 Md. Nur Alam Fethi Bin Muhammad Belgacem M. Ali Akbar 《Journal of Applied Mathematics and Physics》 2015年第12期1571-1579,共9页
The novel (G'/G)-expansion method is a powerful and simple technique for finding exact traveling wave solutions to nonlinear evolution equations (NLEEs). In this article, we study explicit exact traveling wave sol... The novel (G'/G)-expansion method is a powerful and simple technique for finding exact traveling wave solutions to nonlinear evolution equations (NLEEs). In this article, we study explicit exact traveling wave solutions for the (1 + 1)-dimensional combined KdV-mKdV equation by using the novel (G'/G)-expansion method. Consequently, various traveling wave solutions patterns including solitary wave solutions, periodic solutions, and kinks are detected and exhibited. 展开更多
关键词 Novel (G'/G)-Expansion Method (1 %PLUS% 1)-Dimensional COMBINED KdV-mKdV EQUATION Kink Patterns Nonlinear evolution EQUATION Solitary WAVE SOLUTIONS Traveling WAVE SOLUTIONS
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Thoughts of a Medical Doctor about the Life Periods of Our Earth and the Evolution 被引量:1
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作者 Béla Ralovich 《Open Journal of Applied Sciences》 2018年第9期411-421,共11页
The author thinks that the endless and timeless Universe is a permanent substance and energy flow as well as motion of celestial systems and bodies. Celestial bodies may have physical and biological life. Our Earth ha... The author thinks that the endless and timeless Universe is a permanent substance and energy flow as well as motion of celestial systems and bodies. Celestial bodies may have physical and biological life. Our Earth has both lives which can be divided into different periods of time. Its physical life can mainly be characterized by the atomic evolution, sterility, appearance of water and abiotic chemical reactions. Essence of the biological life is the existence of the living unit. Biological life of our Globe started with the first living unit/microorganism which began to influence on its environment which is a closed system for substance, flora, creature and man but not for hit of celestial bodies and for arrival of different kinds of energy from the space as well as for radiation of heat. The biological life of our Earth can be divided into four parts: before photosynthesis, before mankind, before 1778 and after the industrial revolution. 展开更多
关键词 Energy and Substance Flow Physical LIFE Atomic evolution STERILITY Closed System BIOLOGICAL LIFE and Its Effects on the Environment BIOLOGICAL evolution
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Cultural evolution and spatial-temporal distribution of archaeological sites from 9.5–2.3 ka BP in the Yan-Liao region, China 被引量:3
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作者 YUAN Yuying 《Journal of Geographical Sciences》 SCIE CSCD 2019年第3期449-464,共16页
With basic information from 8353 archaeological sites, this study describes a holistic spatial-temporal distribution pattern of archaeological sites of the prehistoric culture sequence from 9.5 ka BP (ka BP = thousand... With basic information from 8353 archaeological sites, this study describes a holistic spatial-temporal distribution pattern of archaeological sites of the prehistoric culture sequence from 9.5 ka BP (ka BP = thousands of years before 0 BP, where "0 BP" is defined as the year AD 1950) to 2.3 ka BP in the region that extends from the Yanshan Mountains to the Liaohe River Plain(i.e., the Yan-Liao region) in northern China. Based on spatial statistics analysis – including the spatial density of the sites and Geographic Information System nearest-neighbour analysis, combined with a review of environmental and climatic data – this paper analyses cultural evolution, the spatial-temporal features of the archaeological sites and human activities against the backdrop of climatic and environmental changes in this region. The results reveal that prehistoric cultural evolution in the Yan-Liao region is extensively influenced by climatic and environmental changes. The Xinglongwa, Zhaobaogou and Fuhe cultures, which primarily developed during a habitable period from 8.5 ka BP to 6.0 ka BP with strong summer monsoons, have similar maximum density values, spatial patterns and subsistence strategies dominated by hunting-gathering. Significant changes occurred in the Hongshan and Lower Xiajiadian cultures, with a significant increase in numbers and densities of sites and a slump in average nearest-neighbour ratio when the environment began to deteriorate starting in 6.0 ka BP. Additionally, with the onset of a weak summer monsoon and the predominance of primitive agriculture, sites of these two cultures present a different type of concentric circle-shaped pattern in space. As the environment continuously deteriorated with increasing aridity and the spread of steppe, more sites were distributed towards the south, and primitive agriculture was replaced by livestock husbandry in the Upper Xiajiadian culture. The most densely populated areas of the studied cultures are centralized within a limited area. The Laohahe River and Jiaolaihe River basins formed the core area in which most archaeological sites were distributed during the strong summer monsoon period and the first few thousand years of the weak summer monsoon period. 展开更多
关键词 PREHISTORIC CULTURAL evolution archaeological site spatial-temporal distribution climate and environmental change Yanshan MOUNTAINS Liaohe River PLAIN
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Corrigendum to “Optimizing the evolution of strength for lime-stabilized rammed soil” [J Rock Mech Geotech Eng 11(2019)882-891]
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作者 Jair de Jesús Arrieta Baldovino Ronaldo Luis dos Santos Izzo +1 位作者 Eclesielter Batista Moreira Juliana Lundgren Rose 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2020年第1期212-212,共1页
The authors regret that in the paper of Baldovino et al.(2019),published in Journal of Rock Mechanics and Geotechnical Engineering(JRMGE),Eq.(2)must be corrected.Eq.(2)in the original paper describes a formula to calc... The authors regret that in the paper of Baldovino et al.(2019),published in Journal of Rock Mechanics and Geotechnical Engineering(JRMGE),Eq.(2)must be corrected.Eq.(2)in the original paper describes a formula to calculate the unconfined compressive strength(q_u).But Authors wrote it as if it were the formula for calculating the split tensile strength(qt).To amend this error,Eq.(1)and Eq.(2)are the correct expressions for q_u and q_t measurements,respectively. 展开更多
关键词 CORRIGENDUM to J ROCK Mech Geotech ENG 11 Optimizing the evolution of strength for lime-stabilized rammed SOIL
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Compact formulation of the augmented evolution equation for optimal control computation
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作者 Sheng Zhang Jiangtao Huang +2 位作者 Gang Liu Fei Liao Fangfang Hu 《Control Theory and Technology》 2026年第1期96-110,共15页
The augmented evolution equation is established under the framework of the Variation Evolving Method(VEM)that seeks optimal solutions by solving the transformed Initial-Value Problems(IVPs).To improve the numerical pe... The augmented evolution equation is established under the framework of the Variation Evolving Method(VEM)that seeks optimal solutions by solving the transformed Initial-Value Problems(IVPs).To improve the numerical performance,its compact form is developed herein.Through replacing the states and costates variation evolution with that of the controls,the dimension-reduced Evolution Partial Differential Equation(EPDE)only solves the control variables along the variation time to get the optimal solution,and the initial conditions for the definite solution may be arbitrary.With this equation,the scale of the resulting IVPs,obtained via the semi-discrete method,is significantly reduced and they may be solved with common Ordinary Differential Equation(ODE)integration methods conveniently.Meanwhile,the state and the costate dynamics share consistent stability in the numerical computation and this avoids the intrinsic numerical difficulty as in the indirect methods.Numerical examples are solved and it is shown that the compact form evolution equation outperforms the primary form in the precision,and the efficiency may be higher for the dense discretization.Actually,it is uncovered that the compact form of the augmented evolution equation is a continuous realization of the Newton type iteration mechanism. 展开更多
关键词 Optimal control Lyapunov dynamics stability Variation evolution evolution partial differential equation Initial-value problem
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Damage evolution and constitutive model of limestone with horizontal fissure under the coupled effects of dry-wet cycling and precompression stress
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作者 Shunbo Zhang Zhongping Yang +2 位作者 Yang Gao Miao Liu Shanmeng Hou 《International Journal of Mining Science and Technology》 2026年第1期205-228,共24页
To reveal the influence of coupled effects of dry-wet cycling and precompression stress(CEDWCPS)on the damage evolution of limestone with horizontal fissure(LHF),a series of degradation and uniaxial compression tests ... To reveal the influence of coupled effects of dry-wet cycling and precompression stress(CEDWCPS)on the damage evolution of limestone with horizontal fissure(LHF),a series of degradation and uniaxial compression tests were conducted,and a corresponding piecewise damage constitutive model(PDCM)was established.We found that both dry-wet cycling and precompression stress deteriorate the physical properties,alter the microscopic characteristics,and reduce the mechanical properties of the LHF.These degradations are particularly pronounced under the CEDWCPS,although the magnitude of these changes gradually diminishes with the progression of dry-wet cycling.Meanwhile,they also reduce the deformation degree,prolong the micropore compaction stage,shorten the unstable crack propagation stage,lower the frequency and intensity of AE events,decrease the high-amplitude and high-frequency AE signals,enlarge crack scales,and shorten the crack initiation time.Among the changes of these indicators,the dry-wet cycling plays a dominant role.The crack types of LHF under the CEDWCPS(LHFCEDWCPS)are predominantly tensile cracks,supplemented by shear cracks.The failure mode can be defined as tensileshear composite failure.Finally,the established PDCM effectively captures the nonlinear deformation of micropore and the linear deformation of the matrix in LHFCEDWCPS,with all corresponding R^(2) consistently exceeding 0.97. 展开更多
关键词 Dry-wet cycling Precompression stress Coupled effect Fractured limestone Damage evolution Damage constitutive model
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Geostress Evolution and Construction Parameter Optimization in Shale Gas Infill Well Development
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作者 Yongjun Xiao Yuduo Sun +5 位作者 Jian Zheng Xiaojin Zhou Wang Liu Cheng Shen Qi Deng Hao Zhao 《Energy Engineering》 2026年第3期152-168,共17页
The shale gas development in China faces challenges such as complex reservoir conditions and high development costs.Based on the pore pressure and geostress coupling theory,this paper studies the geostress evolution l... The shale gas development in China faces challenges such as complex reservoir conditions and high development costs.Based on the pore pressure and geostress coupling theory,this paper studies the geostress evolution laws and fracture network characteristics of shale gas infill wells.A mechanism model of CN platform logging data and geomechanical parameters is established to simulate the influence of parent well’s production on the geostress in the infill well area.It is suggested that with the increase of production time,normal fault stress state and horizontal stress deflection will occur.The smaller the parent well spacing and the longer the production time,the earlier the normal fault stress state appears and the larger the range.Based on the model,the fracture network morphology and construction parameters of infill wells are optimized.parentparentparentparent The results indicate that:1:A well spacing of 500 m achieves a Pareto optimum between“full reserve coverage”and“stress barrier”;2:A parent well recovery degree of 30%corresponds to the critical point of stress reversal,where the lateral deflection rate of the infill fracture is less than 8%and the SRV loss is minimized;3:6-cluster intensive completion with twice the liquid intensity increases the fracture complexity index by 1.7 times,enhances well group EUR by 15.4%,and reduces single-well cost by 22%.This research fills the theoretical gap in the collaborative optimization of“multi-parameter,multi-objective and multi-constraint”and provide parameter optimization basis for shale gas infill well development in China and help to improve the development efficiency and economic benefits. 展开更多
关键词 Shale gas horizontal well geostress evolution infill well development numerical simulation construction parameter optimization
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Sedimentary Characteristics and Evolution of the High-resolution Sequence Stratigraphic Framework of the Taiyuan Formation in the Hangjinqi Area,Northern Ordos Basin
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作者 ZHAO Mingsheng TIAN Jingchun +1 位作者 SU Bingrui ZHANG Xiang 《Acta Geologica Sinica(English Edition)》 2026年第1期54-68,共15页
The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theor... The Ordos Basin is a large superimposed hydrocarbon-bearing basin in China,and further research on the sedimentary characteristics and sedimentary evolution of the sequence framework of target layers is of great theoretical and practical significance for guiding oil and gas exploration.The sedimentary facies and sedimentary evolution of the high-resolution sequence framework of the Carboniferous Taiyuan Formation in the Hangjinqi area have been systematically analyzed for the first time by drilling,logging and seismic data.The results show that four types of sequence interfaces can be identified in the Taiyuan Formation:regional unconformity surfaces,scour surfaces,lithologic-lithofacies transformation surfaces and flooding surfaces.According to the sedimentary response caused by the upward and downward movements of the base level at different levels,the Taiyuan Formation can be divided into 2 long-term cycles(LSC_(1)-LSC_(2)),4 mid-term cycles(MSC_(1)-MSC4)and 7 short-term cycles(SSC_(1)-SSC7).The long-and mid-term cycles correspond to members T_(1)and T_(2)and layers T_(1)-1,T_(1-2),T_(2-1),and T_(2)-2,respectively.Long-term cycles are dominated by C_(1);mid-term cycles are dominated by C_(1)and C_(2),followed by A2;and short-term cycles are dominated by C_(1),C_(2),A1 and A2.Under the high-resolution sequence stratigraphic framework,the Hangjinqi area underwent a transformation of fan delta and tidal flat depositional systems during the Taiyuan Formation sedimentary period.In the MSC_(1)-MSC_(2)stage,owing to a large-scale paleocontinent,the fan delta sedimentary body,which was limited in scale and scope,developed only in the southeastern corner and gradually transitioned basinward to tidal flat facies.In the MSC3-MSC4 stage,as the paleocontinent continuously decreased and the sedimentary range expanded,fan-delta plain sedimentation began in the study area.Several braided distributary channels with poor connectivity developed on the fan-delta plain,and between them were floodplains and peat swamps. 展开更多
关键词 high-resolution sequence framework sedimentary characteristics sedimentary evolution Taiyuan Formation Hangjinqi area northern Ordos Basin
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Evolution and insights of China’s environmental governance policies:An LDA-based policy text analysis
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作者 HUA Yu-chen YANG Jia-meng +2 位作者 WEI Ren-jie CHENG Xiu LIU Zhi-yong 《Ecological Economy》 2026年第1期2-30,共29页
China’s environmental governance strategy provides a distinctive pathway for integrating sustainable development into national policy.Understanding its policy trajectory is essential for assessing China’s contributi... China’s environmental governance strategy provides a distinctive pathway for integrating sustainable development into national policy.Understanding its policy trajectory is essential for assessing China’s contribution to global sustainable development and the United Nations Sustainable Development Goals(SDGs).This study constructs a comprehensive database of 425 national environmental governance policy documents issued between 1978 and 2022 and applies Latent Dirichlet Allocation(LDA)modeling to examine the evolution of policy themes and discourse.The results show that China’s environmental governance has undergone four stages-initial exploration,detailed development,transformative leap,and diverse prosperity-reflecting a progressive shift toward more integrated and coordinated governance.Policy priorities have evolved from a primary focus on pollution control and energy transition to an emphasis on institutional construction and organizational reform,thereby strengthening alignment with the SDGs.This transformation is characterized by recurring developmental themes and increasingly preventive,forward-looking,and system-oriented governance approaches.Moreover,the co-evolution of policy concepts and implementation has driven a transition from localized,end-of-pipe responses to comprehensive governance frameworks,alongside a shift from normative guidance towards effectiveness-oriented policy design.By employing a data-driven text analysis approach,this study offers a systematic framework for tracing long-term policy evolution and assessing its implications for sustainable development. 展开更多
关键词 environmental governance policy text analysis LDA topic modeling topic evolution sustainable development policy policy transformation
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