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World-Universe Model—Alternative to Big Bang Model 认领 引用 被引量：7
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2020年第1期133-158,共26页
This manuscript provides a comparison of the Hypersphere World-Universe Model (WUM) with the prevailing Big Bang Model (BBM) of the Standard Cosmology. The performed analysis of BBM shows that the Four Pillars of the ... This manuscript provides a comparison of the Hypersphere World-Universe Model (WUM) with the prevailing Big Bang Model (BBM) of the Standard Cosmology. The performed analysis of BBM shows that the Four Pillars of the Standard Cosmology are model-dependent and not strong enough to support the model. The angular momentum problem is one of the most critical problems in BBM. Standard Cosmology cannot explain how Galaxies and Extra Solar systems obtained their substantial orbital and rotational angular momenta, and why the orbital momentum of Jupiter is considerably larger than the rotational momentum of the Sun. WUM is the only cosmological model in existence that is consistent with the Law of Conservation of Angular Momentum. To be consistent with this Fundamental Law, WUM discusses in detail the Beginning of the World. The Model introduces Dark Epoch (spanning from the Beginning of the World for 0.4 billion years) when only Dark Matter Particles (DMPs) existed, and Luminous Epoch (ever since for 13.8 billion years). Big Bang discussed in Standard Cosmology is, in our view, transition from Dark Epoch to Luminous Epoch due to Rotational Fission of Overspinning Dark Matter (DM) Supercluster’s Cores. WUM envisions Matter carried from the Universe into the World from the fourth spatial dimension by DMPs. Ordinary Matter is a byproduct of DM annihilation. WUM solves a number of physical problems in contemporary Cosmology and Astrophysics through DMPs and their interactions: Angular Momentum problem in birth and subsequent evolution of Galaxies and Extrasolar systems—how do they obtain it;Fermi Bubbles—two large structures in gamma-rays and X-rays above and below Galactic center;Diversity of Gravitationally-Rounded Objects in Solar system;some problems in Solar and Geophysics [1]. WUM reveals Inter-Connectivity of Primary Cosmological Parameters and calculates their values, which are in good agreement with the latest results of their measurements. 展开更多
关键词 Big Bang Model Four Pillars of Standard Cosmology Angular Momentum Problem Black Holes Hypersphere World-Universe Model Multicomponent Dark Matter Macroobjects Structure Law of Conservation of Angular Momentum Medium of the World Inter-Connectivity of Primary Cosmological Parameters The Beginning of the World Dark Epoch Rotational Fission Luminous Epoch Macroobject Shell Model Dark Matter Core Gravitational Burst Intergalactic Plasma Microwave Background Radiation Far-Infrared Background Radiation Emergent Phenomena CODATA
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Semantic model and optimization of creative processes at mathematical knowledge formation 认领 引用
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作者 Victor Egorovitch Firstov 《Natural Science》 2010年第8期915-922,共8页
The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the ... The aim of this work is mathematical education through the knowledge system and mathematical modeling. A net model of formation of mathematical knowledge as a deductive theory is suggested here. Within this model the formation of deductive theory is represented as the development of a certain informational space, the elements of which are structured in the form of the orientated semantic net. This net is properly metrized and characterized by a certain system of coverings. It allows injecting net optimization parameters, regulating qualitative aspects of knowledge system under consideration. To regulate the creative processes of the formation and realization of mathematical know- edge, stochastic model of formation deductive theory is suggested here in the form of branching Markovian process, which is realized in the corresponding informational space as a semantic net. According to this stochastic model we can get correct foundation of criterion of optimization creative processes that leads to “great main points” strategy (GMP-strategy) in the process of realization of the effective control in the research work in the sphere of mathematics and its applications. 展开更多
关键词 The Cybernetic Conception Optimization of Control Quantitative And Qualitative Information Measures Modelling Intellectual Systems Neural Network Mathematical Education The Control of Pedagogical Processes Creative Pedagogics Cognitive And Creative Processes Informal Axiomatic Thery Semantic Net Net Optimization Parameters The Topology of Semantic Net Metrization The System of Coverings Stochastic Model of Creative Processes At The Formation of Mathematical Knowledge Branching Markovian Process Great Main Points Strategy (GMP-Strategy) of The Creative Processes Control Interdisciplinary Learning: Colorimetric Barycenter
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Mathematical Wave Functions and 3D Finite Element Modelling of the Electron and Positron 认领 引用
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作者 Declan Traill 《Journal of Applied Mathematics and Physics》 2024年第4期1134-1162,共29页
The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric an... The wave/particle duality of particles in Physics is well known. Particles have properties that uniquely characterize them from one another, such as mass, charge and spin. Charged particles have associated Electric and Magnetic fields. Also, every moving particle has a De Broglie wavelength determined by its mass and velocity. This paper shows that all of these properties of a particle can be derived from a single wave function equation for that particle. Wave functions for the Electron and the Positron are presented and principles are provided that can be used to calculate the wave functions of all the fundamental particles in Physics. Fundamental particles such as electrons and positrons are considered to be point particles in the Standard Model of Physics and are not considered to have a structure. This paper demonstrates that they do indeed have structure and that this structure extends into the space around the particle’s center (in fact, they have infinite extent), but with rapidly diminishing energy density with the distance from that center. The particles are formed from Electromagnetic standing waves, which are stable solutions to the Schrödinger and Classical wave equations. This stable structure therefore accounts for both the wave and particle nature of these particles. In fact, all of their properties such as mass, spin and electric charge, can be accounted for from this structure. These particle properties appear to originate from a single point at the center of the wave function structure, in the same sort of way that the Shell theorem of gravity causes the gravity of a body to appear to all originate from a central point. This paper represents the first two fully characterized fundamental particles, with a complete description of their structure and properties, built up from the underlying Electromagnetic waves that comprise these and all fundamental particles. 展开更多
关键词 Electron Positron Wave Function Solution Electromagnetic Spin Mass Charge Proof Fundamental Particle Properties Quantum Mechanics Classical Physics Computer 3D Model Schrödinger Equation RMS Klein Gordon Electric Magnetic Lorentz Invariant Hertzian Vector Point Potential Field Density Phase Flow Attraction Repulsion Shell Theorem Ehrenfest Virial Normalization Harmonic Oscillator
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Model of Universe as Described by Dynamic Universe Model 认领 引用
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作者 Satyavarapu Naga Parameswara Gupta 《Open Journal of Modelling and Simulation》 2019年第1期41-78,共38页
In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the m... In this paper we will see the model of Universe according to Dynamic Universe Model of Cosmology by visualizing various processes that are happening in the Universe as per experimental evidences. For simplifying the matter here, we will see in part 1: about the Galaxy life cycle, where the birth and death of Galaxies discussed. Probably Universe gives guidance for the movement of Galaxies. We call this Part 1: Thinking and Reproducing Universe or Mindless Universe? (Galaxy life cycle). We see every day Sun, Stars, Galaxies etc., dissipating enormous energy in the form of radiation by the way of fusion of Hydrogen to helium. So after sometime all the Hydrogen is spent and Universe will die, is it not? … Dynamic Universe Model says that the energy in the form of electromagnetic radiation passing grazingly near any gravitating mass changes in frequency and finally will convert into neutrinos (mass). Hence Dynamic Universe Model proposes another process where energy will be converted back into matter and the cycle energy to mass to energy continues, sustaining the Universe to maintain this present status for ever in this form something like a Steady state model without any expansion. This we will see in Part 2: Energy - Mass - Energy Cycle. After converting energy into mass “how various elements are formed and where they are formed?” will be next logical question. Dynamic Universe Model says that these various particles change into higher massive particles or may get bombarded into stars or planets and various elements are formed. Here we bifurcate the formation of elements into 6 processes. They are for Elementary particles and elements generated in frequency changing process, By Cosmic rays, By Small stars, By Large Stars, By Super Novae and Manmade elements By Neutron Stars. This we will discuss in Part 3: Nucleosynthesis. 展开更多
关键词 Dynamic Universe Model Hubble Space Telescope (HST) SITA Simulations (SITA-Simulation of Inter Intra Tautness Attraction Forces Used by Dynamic Universe Model) Singularity-Free Cosmology Blue Shifted Galaxies Red Shifted Galaxies Grazing Radiation Frequency Changes Formation of Elements Nucleosynthesis Dynamic Universe Model Energy to Mass Conversion Methods: N-Body Simulations-Gravitation-Cosmology
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Strain and ligand effect on the electronic structure of Ni-Fe and Ni-Cu alloys:Exploring charge redistribution from x-ray spectroscopies and the charge compensation model 认领 引用
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作者 Zeel Patel Lu Yao +5 位作者 Zhiqiang Wang Yun Mui Yiu Tsun-Kong Sham Sarah Purdy Jianfeng Zhu Sammynaiken Ramaswami 《Chinese Physics B》 SCIE EI CAS CSCD 2026年第5期11-20,共10页
Nickel-based bimetallic alloys are considered thermally and structurally stable,while also possessing desirable catalytic and magnetic functionalities and being highly abundant and affordable.The electronic structure ... Nickel-based bimetallic alloys are considered thermally and structurally stable,while also possessing desirable catalytic and magnetic functionalities and being highly abundant and affordable.The electronic structure of such alloys is of particular interest from the perspective of atomic size mismatch and elemental crystal structure compatibility.In this study,we utilize x-ray techniques,including x-ray diffraction(XRD),x-ray absorption spectroscopy(XAS),and x-ray photoelectron spectroscopy(XPS),to understand the strain and ligand effects on charge redistribution upon alloying.We investigate the elemental crystal structures for incompatible alloys of Ni(fcc)and Fe(bcc),and the compatible crystal structure of Ni(fcc)and Cu(fcc)for comparison.Emphasis is placed on interpreting the metal 2p XPS binding energy shift in binary alloys,where one element is diluted into the other,based on the framework of strain and ligand effects and the charge compensation model of Watson et al.Of interest are the different“compressibilities”of the 4s and 3d wavefunctions within the Wigner-Seitz volume,VWS,and the volume-strain effect resulting in intra-atomic 4s-3d rehybridizations within the alloy,as well as the chemical intuition of charge transfer based on the ligand effect(electronegativity).These considerations provide perspective on“internal pressure”due to the strain effect and help in understanding the x-ray data and their correlation with the electronic structures and properties of bimetallic alloy systems. 展开更多
关键词 bimetallic alloys strain and ligand effect renormalized atom charge compensation model x-ray spectroscopy Mössbauer spectroscopy
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Differences in pathological changes between two rat models of severe traumatic brain injury 认领 引用 被引量：9
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作者 Yi-Ming Song Yu Qian +6 位作者 Wan-Qiang Su Xuan-Hui Liu Jin-Hao Huang Zhi-Tao Gong Hong-Liang Luo Chuang Gao Rong-Cai Jiang 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第10期1796-1804,共9页
The rat high-impact free weight drop model mimics the diffuse axonal injury caused by severe traumatic brain injury in humans,while severe controlled cortical impact can produce a severe traumatic brain injury model u... The rat high-impact free weight drop model mimics the diffuse axonal injury caused by severe traumatic brain injury in humans,while severe controlled cortical impact can produce a severe traumatic brain injury model using precise strike parameters.In this study,we compare the pathological mechanisms and pathological changes between two rat severe brain injury models to identify the similarities and differences.The severe controlled cortical impact model was produced by an electronic controlled cortical impact device,while the severe free weight drop model was produced by dropping a 500 g free weight from a height of 1.8 m through a plastic tube.Body temperature and mortality were recorded,and neurological deficits were assessed with the modified neurological severity score.Brain edema and bloodbrain barrier damage were evaluated by assessing brain water content and Evans blue extravasation.In addition,a cytokine array kit was used to detect inflammatory cytokines.Neuronal apoptosis in the brain and brainstem was quantified by immunofluorescence staining.Both the severe controlled cortical impact and severe free weight drop models exhibited significant neurological impairments and body temperature fluctuations.More severe motor dysfunction was observed in the severe controlled cortical impact model,while more severe cognitive dysfunction was observed in the severe free weight drop model.Brain edema,inflammatory cytokine changes and cortical neuronal apoptosis were more substantial and blood-brain barrier damage was more focal in the severe controlled cortical impact group compared with the severe free weight drop group.The severe free weight drop model presented with more significant apoptosis in the brainstem and diffused blood-brain barrier damage,with higher mortality and lower repeatability compared with the severe controlled cortical impact group.Severe brainstem damage was not found in the severe controlled cortical impact model.These results indicate that the severe controlled cortical impact model is relatively more stable,more reproducible,and shows obvious cerebral pathological changes at an earlier stage.Therefore,the severe controlled cortical impact model is likely more suitable for studies on severe focal traumatic brain injury,while the severe free weight drop model may be more apt for studies on diffuse axonal injury.All experimental procedures were approved by the Ethics Committee of Animal Experiments of Tianjin Medical University,China(approval No.IRB2012-028-02)in Febru ary 2012. 展开更多
关键词 nerve regeneration severe traumatic brain injury animal model comparison free weight drop controlled cortical impact neurological impairment neuroinflammation blood-brain barrier damage neuronal apoptosis diffuse axonal injury brainstem injury neural regeneration
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Neurotoxicity,α-synuclein pathology,and mitochondrial dysfunction:A comparative study of different mouse models of Parkinson's disease 认领 引用 被引量：2
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作者 Xiwen Tang Yifei He +9 位作者 Min Liang Penggang Ning Jiayin Zhao Yunhe Zhang Xin Yan Ruilin Sun Gang Wei Ruling Shen Fang Huang Mei Yu 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第10期5000-5012,共13页
The causes of Parkinson's disease are complex,and it is difficult for a single animal model to fully mimic its pathological characteristics.In this study,a comprehensive analysis of behaviors,Parkinson's disea... The causes of Parkinson's disease are complex,and it is difficult for a single animal model to fully mimic its pathological characteristics.In this study,a comprehensive analysis of behaviors,Parkinson's disease-like pathologies,and gene and protein expression profiles was carried out in three mouse models of disease:1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced,α-synuclein(α-syn)A53T transgenic,and Mito Park,revealing both shared and model-specific pathogenic pathways to guide model selection and identify potential therapeutic targets.All three Parkinson's disease models exhibited motor impairments,with particularly pronounced age-related decline observed in Mito Park mice.Pathologically,nigrostriatal pathway damage was observed in all models,yet with distinct patterns of glial cell activation.Sixteen-month-oldα-syn A53T mice displayed a few p S129-α-syn-positive signals in the substantia nigra,while noα-syn aggregates were observed in any of the models.RNA sequencing and proteomics analysis revealed significant changes in gene and protein expression,with both unique and common features among the three models.Five common differentially expressed genes(Ifi27l2a,Ifitm3,Oasl2,Rtp4,and Ankk1)and two common differentially expressed proteins(Timm8a1 and Sephs1)were identified.Functional enrichment analysis indicated that immune responses,cytokines,and neurotransmitter transport were crucial in Parkinson's disease pathogenesis.Notably,multiple iron-related cell damage(ferroptosis)-related differentially expressed genes were identified across all three models,while interleukin 17 pathway activation was altered in Mito Park mice.In summary,we analyzed the commonalities and specificities of pathological simulation capabilities and common disease mechanisms in different mouse models of Parkinson's disease from multiple perspectives.Our findings offer valuable insights into the multifaceted characteristics of Parkinson's disease and will assist in model selection for mechanistic exploration in the future. 展开更多
关键词 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced model ferroptosis pathway glial cell activation interleukin 17 pathway mitochondrial dysfunction MitoPark model nerve regeneration neurodegeneration nigrostriatal pathway pS129-α-syn α-syn A53T transgenic model
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Spatial distribution patterns and hazard assessment of co-seismic landslides triggered by the 2022 Luding earthquake(MS 6.8):An RF-AdaBoost model approach 认领 引用
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作者 Li-ying Gu Guo-liang Du +1 位作者 Ling Zou Xin Wang 《China Geology》 CAS CSCD 2026年第2期349-365,共17页
On September 5,2022,a magnitude 6.8 earthquake struck Luding County,Sichuan Province,China,at a depth of 16 km,triggering numerous co-seismic landslides.Using multi-temporal satellite imagery,the authors identified 74... On September 5,2022,a magnitude 6.8 earthquake struck Luding County,Sichuan Province,China,at a depth of 16 km,triggering numerous co-seismic landslides.Using multi-temporal satellite imagery,the authors identified 7463 co-seismic landslides with varying spatial distributions.Focusing on the differences between the western and eastern sections of the Xianshuihe fault zone,the influences of elevation,slope,aspect,topographic wetness index(TWI),stream power index(SPI),distance to river,distance to seismogenic fault,seismic intensity,lithology,and land surface temperature(LST)on the coseismic landslide distribution were analyzed.Random Forest-Adaptive Boosting(RF-AdaBoost),Support Vector Machine(SVM)and Back Propagation Neural Network(BP)models were used to assess landslide hazards in the region.The RF-AdaBoost model performed the best,achieving an Area Under the Curve(AUC)of 0.954.The zones of high co-seismic landslide hazard were primarily concentrated along the Xianshuihe fault zone and Dadu River.These findings provide valuable insights into seismic landslide hazard assessments and offer scientific guidance for disaster prevention and mitigation strategies. 展开更多
关键词 Luding earthquake(MS 6.8) Co-seismic landslides(7463) Landslide distribution Multi-temporal satellite imagery RF-AdaBoost model SVM model BP model Hazard assessment Xianshuihe fault zone Geological disaster prevention and control engineering
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World-Universe Model Predictions 认领 引用 被引量：7
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2020年第2期282-297,共16页
In 2013, World-Universe Model (WUM) proposed a principally different way to solve the problem of Newtonian Constant of Gravitation measurement precision. WUM revealed a self-consistent set of time-varying values of Pr... In 2013, World-Universe Model (WUM) proposed a principally different way to solve the problem of Newtonian Constant of Gravitation measurement precision. WUM revealed a self-consistent set of time-varying values of Primary Cosmological parameters of the World: Gravitation parameter, Hubble’s parameter, Age of the World, Temperature of the Microwave Background Radiation, and the concentration of Intergalactic plasma. Based on the inter-connectivity of these parameters, WUM solved the Missing Baryon problem and predicted the values of the following Cosmological parameters: gravitation G, concentration of Intergalactic plasma, relative energy density of protons in the Medium, and the minimum energy of photons, which were experimentally confirmed in 2015-2018. Between 2013 and 2018, the relative standard uncertainty of G measurements decreased x6. The set of values obtained by WUM was recommended for consideration in CODATA Recommended Values of the Fundamental Physical Constants 2014. 展开更多
关键词 World-Universe Model Dimensionless Time-Varying Parameter Q Gravitational Parameter Hubble’s Parameter Age of the World Temperature of Microwave Background Radiation Temperature of Far-Infrared Background Radiation Peak Medium of the World Inter-Connectivity of Primary Cosmological Parameters Multicomponent Dark Matter Weak Interaction Intergalactic Plasma Neutrinos CODATA
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From Lexicons to Large Language Models:A Comprehensive Survey of Sentiment Analysis Methods,Benchmarks,and Emerging Frontiers 认领 引用
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作者 Shuvodeep De Agnivo Gosai +4 位作者 Karun Thankachan Ramadan A.Zein Eldin Abdulaziz T.Almaktoom Mustafa Bayram Ali Wagdy Mohamed 《Computer Modeling in Engineering & Sciences》 SCIE EI 2026年第5期119-167,共49页
Sentiment analysis(SA)has evolved from a niche text-classification task into a central problem in natural language processing,spanning multiple domains,modalities,and languages.This survey provides a comprehensive rev... Sentiment analysis(SA)has evolved from a niche text-classification task into a central problem in natural language processing,spanning multiple domains,modalities,and languages.This survey provides a comprehensive review of sentiment analysis methods from their origins in lexicon-based approaches through classical machine learning,deep learning architectures,pre-trained transformers,and the current era of large language models(LLMs).We formalize the SA problem across multiple granularity levels(document,sentence,and aspect)and present a taxonomy that encompasses classification,regression,aspect-based sentiment analysis(ABSA),emotion detection,and stance detection tasks across diverse domains including movie reviews,product reviews,healthcare,finance,and social media.We review benchmark datasets spanning text-only corpora(IMDb,SST,SemEval series),multimodal benchmarks(CMU-MOSI,CMU-MOSEI,MELD),and domain-specific evaluation suites such as SentiEval.The methodological evolution is traced from VADER and SentiWordNet,through SVM and Naïve Bayes classifiers,CNN and LSTM architectures,BERT and its variants,to modern LLMs including GPT-4,Llama 3,and ModernBERT,with technical details of key architectures and their mathematical formulations.We provide dedicated analyses of chain-ofthought reasoning for implicit sentiment,multimodal fusion strategies,cross-lingual transfer methods,sarcasm and irony detection,explainability through SHAP and LIME,and the emerging challenge of AI-generated fake reviews.A comparative analysis across paradigms reveals that while LLMs achieve strong zero-shot performance,fine-tuned smaller models remain competitive on standard benchmarks,a finding with significant implications for deployment efficiency.We identify persistent open challenges including domain drift,cultural bias,and the model variability problem,and outline future research directions encompassing reasoning-augmented SA,agentic workflows,federated learning,and real-time edge deployment.With coverage of over 130 references spanning two decades of research and 29 new references from 2024 and 2025,this survey provides a unified roadmap for both newcomers and researchers at the frontier of sentiment analysis. 展开更多
关键词 Sentiment analysis opinion mining large language models transformers BERT aspect-based sentiment analysis multimodal sentiment analysis cross-lingual NLP explainable AI chain-of-thought reasoning sarcasm detection benchmark datasets
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Centrifuge modeling study on near-ground explosions and the coupling of ground shock energy in sandy foundation 认领 引用
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作者 Longhua Guan Zheng Pang +3 位作者 Qiang Lu Yang Ding Yubing Wang Yunmin Chen 《Defence Technology（防务技术）》 SCIE EI CAS CSCD 2026年第7期93-109,共17页
Blast effects and energy transfer in near-ground explosions differ significantly from underground scenarios,particularly in terms of ground shock propagation and energy coupling mechanisms across various geological co... Blast effects and energy transfer in near-ground explosions differ significantly from underground scenarios,particularly in terms of ground shock propagation and energy coupling mechanisms across various geological conditions.This study employs centrifuge modeling to simulate near-ground explosions in sandy soil,including surface explosions and airbursts.The focus was on blast-induced cratering,ground shock effects,and energy coupling in sandy foundations.Scaling laws for crater dimensions and ground shock parameters were established and validated based on experimental results.The"modeling of models"series showed good consistency in crater measurements,leading to an empirical formula for estimating crater radius in dry sand.For surface explosions,soil acceleration responses showed single peaks in the central zone(horizontal standoff distance<0.6 m/(kg)1/3)and dual peaks in the near-surface zone(0.79-1.2 m/(kg)1/3)due to combined effects of direct and airburst-induced ground shock.Empirical methods were developed to predict peak acceleration distributions in sandy foundations.Utilizing crater measurements and ground shock propagation laws,a computational approach for evaluating energy transmission in soil foundations was proposed.The study also developed prediction curves for ground shock energy coupling coefficients with scaled blast depth/height,providing a unified model for both underground and near-ground explosions in sandy foundations.The research findings can enhance the methodologies for simulating blast effects and offer a scientific basis for optimizing weapon effectiveness and protective engineering design. 展开更多
关键词 Centrifuge model tests Near-ground explosions Explosion-induced cratering Ground shock Energy coupling
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Stochastic discrete event simulation for government assisted owner driven participatory housing recovery modeling:Application to 2015 Gorkha earthquake sequence,Nepal 认领 引用
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作者 Dipendra Gautam Sajan KC Olafur Petur Palsson 《Resilient Cities and Structures》 EI CSCD 2026年第1期45-59,共15页
We develop and implement a Stochastic Discrete Event Simulation(SDES)algorithm to model the housing re-covery trajectory after an extreme event.The algorithm models discrete events and their underlying uncertainties i... We develop and implement a Stochastic Discrete Event Simulation(SDES)algorithm to model the housing re-covery trajectory after an extreme event.The algorithm models discrete events and their underlying uncertainties in each construction phase.Specifically,the algorithm is developed for the Government Assisted Owner Driven(GAOD)reconstruction system to simulate long-term recovery trajectory.SDES,as a flexible modeling approach,can simulate any housing recovery scenario that follows phased reconstruction.The 2015 M 7.8 Gorkha earthquake sequence in Nepal is considered the extreme event,with 796,245 buildings requiring reconstruction.We present some recovery trajectories from severely hit,crisis hit,and earthquake hit parishes,comparing them with the actual reconstruction progress.We also assess quality and improvement of reconstructed buildings using seismic fragility functions,compared to pre-earthquake constructions.Housing recovery uncertainties are dissected in relation to reconstruction pace.We conclude that the vast majority of the reconstructed buildings followed the Build Back Better(BBB)approach and missed the opportunity to pursue the Build Back Resilient(BBR)approach due to multifaceted challenges ranging from unclear policies to economic constraints.We critically assess the GAOD vs Owner Driven(OD)recovery framework and conclude that insurance-supported and technically assisted OD approach could be the most suitable model for post extreme event housing recovery. 展开更多
关键词 Stochastic modeling Discrete event simulation Participatory reconstruction Housing recovery Community resilience Earthquake damage Reinforced concrete Stone masonry Brick masonry Seismic vulnerability Gorkha earthquake sequence
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Establishment and verification of a surgical prognostic model for cervical spinal cord injury without radiological abnormality 认领 引用 被引量：7
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作者 Jie Wang Shuai Guo +2 位作者 Xuan Cai Jia-Wei Xu Hao-Peng Li 《Neural Regeneration Research》 SCIE CAS CSCD 2019年第4期713-720,共8页
Some studies have suggested that early surgical treatment can effectively improve the prognosis of cervical spinal cord injury without radiological abnormality, but no research has focused on the development of a prog... Some studies have suggested that early surgical treatment can effectively improve the prognosis of cervical spinal cord injury without radiological abnormality, but no research has focused on the development of a prognostic model of cervical spinal cord injury without radiological abnormality. This retrospective analysis included 43 patients with cervical spinal cord injury without radiological abnormality. Seven potential factors were assessed: age, sex, external force strength causing damage, duration of disease, degree of cervical spinal stenosis, Japanese Orthopaedic Association score, and physiological cervical curvature. A model was established using multiple binary logistic regression analysis. The model was evaluated by concordant profiling and the area under the receiver operating characteristic curve. Bootstrapping was used for internal validation. The prognostic model was as follows: logit(P) =-25.4545 + 21.2576 VALUE + 1.2160SCORE-3.4224 TIME, where VALUE refers to the Pavlov ratio indicating the extent of cervical spinal stenosis, SCORE refers to the Japanese Orthopaedic Association score(0–17) after the operation, and TIME refers to the disease duration(from injury to operation). The area under the receiver operating characteristic curve for all patients was 0.8941(95% confidence interval, 0.7930–0.9952). Three factors assessed in the predictive model were associated with patient outcomes: a great extent of cervical stenosis, a poor preoperative neurological status, and a long disease duration. These three factors could worsen patient outcomes. Moreover, the disease prognosis was considered good when logit(P) ≥-2.5105. Overall, the model displayed a certain clinical value. This study was approved by the Biomedical Ethics Committee of the Second Affiliated Hospital of Xi'an Jiaotong University, China(approval number: 2018063) on May 8, 2018. 展开更多
关键词 nerve regeneration surgical prognostic model cervical spinal cord injury retrospective study multiple binary logistic regression analysis bootstrapping internal validation multiple imputations cervical spinal stenosis duration of disease Pavlov ratio neural regeneration
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Permeability evolution and model of methane hydrate-bearing sediments under coupled shear strain,effective confining pressure,and hydrate saturation 认领 引用
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作者 Tian-xiang Ao Le Zhao +3 位作者 Ming-zhong Gao Meng Xu Yi-kun Yang Ming-zhu Qi 《China Geology》 CAS CSCD 2026年第3期584-595,共12页
The permeability of methane hydrate-bearing sediments(MHBS)is a key parameter for evaluating reservoir exploitation potential and formulating efficient production strategies.In actual field development,MHBS exists in ... The permeability of methane hydrate-bearing sediments(MHBS)is a key parameter for evaluating reservoir exploitation potential and formulating efficient production strategies.In actual field development,MHBS exists in a complex environment characterized by stress-seepage coupling.Research on the permeability model of methane hydrate-bearing sediments under multi-factor coupling conditions remains scarce,limiting the assessment of methane hydrate(MH)reservoir hydrocarbon production potential and efficient development.This study used quartz sand and deep-sea clay from the South China Sea as matrix materials to generate MH,simulating MHBS.Systematic triaxial seepage experiments were conducted to assess the influence of multiple factors,including triaxial shear process,effective confining pressure,and hydrate saturation,on the permeability characteristics of MHBS.The results demonstrate the following:(1)During triaxial compression,permeability exhibits a nonlinear variation—first decreasing and then stabilizing or rebounding—with increasing shear strain,reflecting stress-induced pore structure evolution;(2)the permeability of MHBS decreases nonlinearly with increasing effective confining pressure,showing higher sensitivity in the low-pressure range.Effective confining pressure reduces sample permeability by compressing seepage channels,and this effect is more significant at the initial stages of stress growth;(3)hydrate saturation is negatively correlated with permeability,with the cementing effect of hydrates being the primary cause for the decrease in permeability of MHBS,also reducing the impact of effective confining pressure;(4)effective confining pressure,hydrate saturation,and shear strain have a coupled effect,jointly influencing the permeability of MHBS,but their relative weights vary and require specific consideration;(5)based on experimental data,a permeability prediction model considering the coupling effects of shear strain,effective confining pressure,and hydrate saturation was established.This model demonstrates excellent predictive accuracy and can be applied to forecast the hydrocarbon yield potential of MHBS under varying geological and engineering conditions,providing quantitative basis for reservoir evaluation and gas production prediction.This study bridges the gap between laboratory permeability characterization and field production capacity forecasting,offering critical theoretical and technical support for the sustainable development of marine gas hydrate resources. 展开更多
关键词 Hydrate Clean enegy Combustible ice Unconventional energy Exploitation potential assessment Hydrate-bearing sediments Triaxial test Hydrate saturation Effective confining pressure Shear strain Permeability evolution Seepage mechanism Multi-factor coupling model
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Multi-model comparison of CO2 emissions peaking in China:Lessons from CEMF01 study 认领 引用 被引量：7
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作者 Oleg LUGOVOY FENG Xiang-Zhao +4 位作者 GAO Ji LI Ji-Feng LIU Qiang TENG Fei ZOU Le-Le 《Advances in Climate Change Research》 SCIE CSCD 2018年第1期1-15,共15页
The paper summarizes results of the China Energy Modeling Forum's(CEMF)first study.Carbon emissions peaking scenarios,consistent with China's Paris commitment,have been simulated with seven national and indust... The paper summarizes results of the China Energy Modeling Forum's(CEMF)first study.Carbon emissions peaking scenarios,consistent with China's Paris commitment,have been simulated with seven national and industry-level energy models and compared.The CO2 emission trends in the considered scenarios peak from 2015 to 2030 at the level of 9e11 Gt.Sector-level analysis suggests that total emissions pathways before 2030 will be determined mainly by dynamics of emissions in the electric power industry and transportation sector.Both sectors will experience significant increase in demand,but have low-carbon alternative options for development.Based on a side-by-side comparison of modeling input and results,conclusions have been drawn regarding the sources of emissions projections differences,which include data,views on economic perspectives,or models'structure and theoretical framework.Some suggestions have been made regarding energy models'development priorities for further research. 展开更多
关键词 Carbon emissions projections Climate change CO2 emissions peak China’s Paris commitment Top-Down energy models Bottom-Up energy models Multi model comparative study China Energy Modeling Forum(CEMF)
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Human cerebral organoids:Complex,versatile,and human-relevant models of neural development and brain diseases 认领 引用 被引量：3
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作者 Raquel Coronel Rosa González-Sastre +8 位作者 Patricia Mateos-Martínez Laura Maeso Elena Llorente-Beneyto Sabela Martín-Benito Viviana S.Costa Gagosian Leonardo Foti Ma Carmen González-Caballero Victoria López-Alonso Isabel Liste 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第3期837-854,共18页
The brain is the most complex human organ,and commonly used models,such as two-dimensional-cell cultures and animal brains,often lack the sophistication needed to accurately use in research.In this context,human cereb... The brain is the most complex human organ,and commonly used models,such as two-dimensional-cell cultures and animal brains,often lack the sophistication needed to accurately use in research.In this context,human cerebral organoids have emerged as valuable tools offering a more complex,versatile,and human-relevant system than traditional animal models,which are often unable to replicate the intricate architecture and functionality of the human brain.Since human cerebral organoids are a state-of-the-art model for the study of neurodevelopment and different pathologies affecting the brain,this field is currently under constant development,and work in this area is abundant.In this review,we give a complete overview of human cerebral organoids technology,starting from the different types of protocols that exist to generate different human cerebral organoids.We continue with the use of brain organoids for the study of brain pathologies,highlighting neurodevelopmental,psychiatric,neurodegenerative,brain tumor,and infectious diseases.Because of the potential value of human cerebral organoids,we describe their use in transplantation,drug screening,and toxicology assays.We also discuss the technologies available to study cell diversity and physiological characteristics of organoids.Finally,we summarize the limitations that currently exist in the field,such as the development of vasculature and microglia,and highlight some of the novel approaches being pursued through bioengineering. 展开更多
关键词 assembloids bioengineering challenges disease modeling drug screening and toxicology human brain organoids human pluripotent stem cells neurodegenerative diseases neurodevelopment vascularization
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H_∞ Optimal Model Reduction for Singular Fast Subsystems 认领 引用
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作者 WANGJing ZHANGQing-Ling +1 位作者 LIUWan-Quan ZHOUYue 《自动化学报》 EI CAS 北大核心 2005年第4期638-641,共4页
In this paper, H∞ optimal model reduction for singular fast subsystems will be inves-tigated. First, error system is established to measure the error magnitude between the original andreduced systems, and it is demon... In this paper, H∞ optimal model reduction for singular fast subsystems will be inves-tigated. First, error system is established to measure the error magnitude between the original andreduced systems, and it is demonstrated that the new feature for model reduction of singular systemsis to make H∞ norm of the error system finite and minimal. The necessary and su?cient conditionis derived for the existence of the H∞ suboptimal model reduction problem. Next, we give an exactand practicable algorithm to get the parameters of the reduced subsystems by applying the matrixtheory. Meanwhile, the reduced system may be also impulsive. The advantages of the proposedalgorithm are that it is more ?exible in a straight-forward way without much extra computation, andthe order of the reduced systems is as minimal as possible. Finally, one illustrative example is givento illustrate the e?ectiveness of the proposed model reduction approach. 展开更多
关键词 for Model Fast systems model matrix the First and fast norm mini Next more The is to new get may are one be it
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A Model for the Mass-Growth of Wild-Caught Fish 认领 引用 被引量：1
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作者 Katharina Renner-Martin Norbert Brunner +2 位作者 Manfred Kühleitner Werner-Georg Nowak Klaus Scheicher 《Open Journal of Modelling and Simulation》 2019年第1期19-40,共22页
The paper searched for raw data about wild-caught fish, where a sigmoidal growth function described the mass growth significantly better than non-sigmoidal functions. Specifically, von Bertalanffy’s sigmoidal growth ... The paper searched for raw data about wild-caught fish, where a sigmoidal growth function described the mass growth significantly better than non-sigmoidal functions. Specifically, von Bertalanffy’s sigmoidal growth function (metabolic exponent-pair a = 2/3, b = 1) was compared with unbounded linear growth and with bounded exponential growth using the Akaike information criterion. Thereby the maximum likelihood fits were compared, assuming a lognormal distribution of mass (i.e. a higher variance for heavier animals). Starting from 70+ size-at-age data, the paper focused on 15 data coming from large datasets. Of them, six data with 400 - 20,000 data-points were suitable for sigmoidal growth modeling. For these, a custom-made optimization tool identified the best fitting growth function from the general von Bertalanffy-Pütter class of models. This class generalizes the well-known models of Verhulst (logistic growth), Gompertz and von Bertalanffy. Whereas the best-fitting models varied widely, their exponent-pairs displayed a remarkable pattern, as their difference was close to 1/3 (example: von Bertalanffy exponent-pair). This defined a new class of models, for which the paper provided a biological motivation that relates growth to food consumption. 展开更多
关键词 Growth Models Described by the von Bertalanffy-Pütter Differential Equation Model Selection Using the Akaike Information Criterion Maximum Likelihood Fit Based on a Lognormal Distribution of Mass Optimization Using Simulated Annealing
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Intelligent Agent Based Mapping of Software Requirement Specification to Design Model 认领 引用
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作者 Emdad Khan Mohammed Alawairdhi 《Journal of Software Engineering and Applications》 2013年第12期630-637,共8页
Automatically mapping a requirement specification to design model in Software Engineering is an open complex problem. Existing methods use a complex manual process that use the knowledge from the requirement specifica... Automatically mapping a requirement specification to design model in Software Engineering is an open complex problem. Existing methods use a complex manual process that use the knowledge from the requirement specification/modeling and the design, and try to find a good match between them. The key task done by designers is to convert a natural language based requirement specification (or corresponding UML based representation) into a predominantly computer language based design model—thus the process is very complex as there is a very large gap between our natural language and computer language. Moreover, this is not just a simple language conversion, but rather a complex knowledge conversion that can lead to meaningful design implementation. In this paper, we describe an automated method to map Requirement Model to Design Model and thus automate/partially automate the Structured Design (SD) process. We believe, this is the first logical step in mapping a more complex requirement specification to design model. We call it IRTDM (Intelligent Agent based requirement model to design model mapping). The main theme of IRTDM is to use some AI (Artificial Intelligence) based algorithms, semantic representation using Ontology or Predicate Logic, design structures using some well known design framework and Machine Learning algorithms for learning over time. Semantics help convert natural language based requirement specification (and associated UML representation) into high level design model followed by mapping to design structures. AI method can also be used to convert high level design structures into lower level design which then can be refined further by some manual and/or semi automated process. We emphasize that automation is one of the key ways to minimize the software cost, and is very important for all, especially, for the “Design for the Bottom 90% People” or BOP (Base of the Pyramid People). 展开更多
关键词 Software Engineering Artificial Intelligence Ontology Intelligent Agent Requirements Specification Requirements Modeling Design Modeling Semantics Natural Language Understanding Machine Learning Universal Modeling Language (UML) ICT (Information and Communication Technology and BOP (Base of the Pyramid People)
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Astrophysics: Macroobject Shell Model 认领 引用 被引量：8
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2017年第4期776-790,共15页
The model proposes that Nuclei of all macroobjects (Galaxy clusters, Galaxies, Star clusters, Extrasolar systems) are made up of Dark Matter Particles (DMP). These Nuclei are surrounded by Shells composed of both Dark... The model proposes that Nuclei of all macroobjects (Galaxy clusters, Galaxies, Star clusters, Extrasolar systems) are made up of Dark Matter Particles (DMP). These Nuclei are surrounded by Shells composed of both Dark and Baryonic matter. This model is used to explain various astrophysical phenomena: Multi-wavelength Pulsars;Binary Millisecond Pulsars;Gamma-Ray Bursts;Fast Radio Bursts;Young Stellar Object Dippers;Starburst Galaxies;Gravitational Waves. New types of Fermi Compact Stars made of DMP are introduced: Neutralino star, WIMP star, and DIRAC star. Gamma-Ray Pulsars are rotating Neutralino and WIMP stars. Merger of binary DIRAC stars can be a source of Gravitational waves. 展开更多
关键词 Hypersphere World-Universe Model Medium of the World Macroobject Shell Model Dark Matter Particles Gamma-Ray Bursts Fast Radio Bursts Multiwavelength Pulsars Binary Millisecond Pulsars Young Stellar Object Dippers Starburst Galaxies Gravitational Waves
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