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Hypersphere World-Universe Model. Tribute to Classical Physics 被引量:6
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2018年第3期441-470,共30页
This manuscript summarizes the results of Classical Physics before Quantum Mechanics and Hypotheses proposed by classical physicists from the 17th until the beginning of 21st century. We then proceed to unify these re... This manuscript summarizes the results of Classical Physics before Quantum Mechanics and Hypotheses proposed by classical physicists from the 17th until the beginning of 21st century. We then proceed to unify these results into a single coherent picture in frames of the developed Hypersphere World-Universe Model (WUM). The Model proposes 5 types of Dark Matter particles and predicts their masses;models the origin, evolution, and structure of the World and Macroobjects;provides a mathematical framework that ties together a number of Fundamental constants and allows for direct calculation of their values. 展开更多
关键词 Classical Physics HYPERSPHERE World-Universe model Medium of the World Dark Matter Particles Gravitoelectromagnetism COSMIC NEUTRINO Background Macroobjects Structure Emergent Phenomena Q-Dependent COSMOLOGICAL Parameters
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5D World-Universe Model. Multicomponent Dark Matter 被引量:4
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2015年第2期55-71,共17页
5D World-Universe Model (WUM) is based on the decisive role of the Medium of the World com-posed of massive particles: protons, electrons, photons, neutrinos, and Dark Matter Particles (DMP). The model forecasts the m... 5D World-Universe Model (WUM) is based on the decisive role of the Medium of the World com-posed of massive particles: protons, electrons, photons, neutrinos, and Dark Matter Particles (DMP). The model forecasts the masses of DMP, discusses the possibility of all macroobject cores consisting of DMP (galaxy clusters, galaxies, star clusters, extrasolar systems, and planets), and explains the diffuse cosmic gamma-ray background radiation as the sum of contributions of multicomponent dark matter annihilation. The signatures of DMP annihilation with expected masses of 1.3 TeV, 9.6 GeV, 70 MeV, 340 keV, and 3.7 keV, are found in spectra of the diffuse gamma-ray background and the emission of various macroobjects in the World. The correlation between different emission lines in spectra of macroobjects is connected to their structure, which depends on the composition of the cores and surrounding shells made up of DMP. Consequently, the diversity of Very High Energy (VHE) gamma-ray sources in the World has a clear explanation. 展开更多
关键词 5D World-Universe model Medium of the World Dark Matter Particles CORES of Macroobjects GAMMA-RAY Background Radiation PIONEER ANOMALY
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The integration of nitrogen dynamics into a land surface model. Part 1: model description and site-scale validation 被引量:2
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作者 YANG Xiujing DAN Li +5 位作者 YANG Fuqiang PENG Jing LI Yueyue GAO Dongdong JI Jinjun HUANG Mei 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第1期50-57,共8页
Nitrogen cycling has profound effects on carbon uptake in the terrestrial ecosystem and the response of the biosphere to climate changes.However,nutrient cycling is not taken into account in most land surface models f... Nitrogen cycling has profound effects on carbon uptake in the terrestrial ecosystem and the response of the biosphere to climate changes.However,nutrient cycling is not taken into account in most land surface models for climate change.In this study,a nitrogen model,based on nitrogen transformation processes and nitrogen fluxes exchange between the atmosphere and terrestrial ecosystem,was incorporated into the Atmosphere–Vegetation Interaction Model(AVIM)to simulate the carbon cycle under nitrogen limitation.This new model,AVIM-CN,was evaluated against site-scale eddy covariance–based measurements of an alpine meadow located at Damxung station from the FLUXNET 2015 dataset.Results showed that the annual mean gross primary production simulated by AVIM-CN(0.7073 gC m^-2 d^-1)was in better agreement with the corresponding flux data(0.5407 gC m^-2 d^-1)than the original AVIM(1.1403 gC m^-2 d^-1)at Damxung station.Similarly,ecosystem respiration was also down-regulated,from 1.7695 gC m^-2 d^-1 to 1.0572 gC m^-2 d^-1,after the nitrogen processes were introduced,and the latter was closer to the observed vales(0.8034 gC m^-2 d^-1).Overall,the new results were more consistent with the daily time series of carbon and energy fluxes of observations compared to the former version without nitrogen dynamics.A model that does not incorporate the limitation effects of nitrogen nutrient availability will probably overestimate carbon fluxes by about 40%. 展开更多
关键词 Coupled carbon and nitrogen dynamics nitrogen limitation land surface model carbon–nitrogen–water cycles
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Structure of Essential Spectrum and Discrete Spectra of the Energy Operator of Five-Electron Systems in the Hubbard Model. Third and Fourth Doublet States 被引量:1
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作者 S. M. Tashpulatov 《Journal of Applied Mathematics and Physics》 2020年第12期2886-2918,共33页
We consider a five-electron system in the Hubbard model with a coupling between nearest-neighbors. The structure of essential spectrum and discrete spectrum of the systems in the third and fourth doublet states in a &... We consider a five-electron system in the Hubbard model with a coupling between nearest-neighbors. The structure of essential spectrum and discrete spectrum of the systems in the third and fourth doublet states in a <em>v</em>-dimensional lattice is investigated. We prove that the essential spectrum of the system in a third doublet state consists is the union of at most four segments, and discrete spectrum of the system is empty. We show that the essential spectrum of the system in a fourth doublet state consists of the union of at most seven segments, and discrete spectrum of the system consists of no more than one point. 展开更多
关键词 Essential Spectrum Discrete Spectrum Five-Electron System Bound State Anti-Bound State Hubbard model Doublet State Sextet State Quartet State
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5D World-Universe Model. Gravitation 被引量:11
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2016年第3期328-343,共16页
5D World-Universe Model is based on the decisive role of the Medium of the World composed of massive particles: protons, electrons, photons, neutrinos, and dark matter particles. In this manuscript we discuss differen... 5D World-Universe Model is based on the decisive role of the Medium of the World composed of massive particles: protons, electrons, photons, neutrinos, and dark matter particles. In this manuscript we discuss different aspects of the gravitation: measured values of the Newtonian parameter of Gravitation and different Gravitational effects (gravitational lensing, cosmological redshift, gravitational deflection of light and gravitational refraction, proposed in the present paper). We show inter-connectivity of all cosmological parameters and provide a mathematical framework that allows direct calculation of them based on the value of the gravitational parameter. We analyze the difference between Electromagnetism and Gravitoelectromagnetism and make a conclusion about the mandatory existence of the Medium of the World. This paper aligns the World-Universe Model with the Le Sage’s theory of gravitation and makes a deduction on Gravity, Space and Time be emergent phenomena. 展开更多
关键词 5D World-Universe model Newtonian Parameter of Gravitation Le Sage’s Gravity Cosmic Neutrino Background Gravitoelectromagnetism Medium of the World Cosmological Parameters Emergent Phenomena
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5D World-Universe Model. Neutrinos. The World 被引量:9
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 2016年第1期1-18,共18页
In this manuscript we discuss mass-varying neutrinos and propose their energy density to exceed that of baryonic and dark matter. We introduce cosmic Large Grains whose mass is about Planck mass, and their temperature... In this manuscript we discuss mass-varying neutrinos and propose their energy density to exceed that of baryonic and dark matter. We introduce cosmic Large Grains whose mass is about Planck mass, and their temperature is around 29 K. Large Grains are in fact Bose-Einstein condensates of proposed dineutrinos, and are responsible for the cosmic Far-Infrared Background (FIRB) radiation. The distribution of the energy density of all components of the World (protons, electrons, photons, neutrinos, and dark matter particles) is considered. We present an overview of the World- Universe Model (WUM) and pay particular attention to the self-consistent set of time-varying values of basic parameters of the World: the age and critical energy density;Newtonian parameter of gravitation and Hubble’s parameter;temperatures of the cosmic Microwave Background radiation and the peak of the cosmic FIRB radiation;Fermi coupling parameter and coupling parameters of the proposed Super-Weak and Extremely-Weak interactions. Additionally, WUM forecasts the masses of dark matter particles, axions, and neutrinos;proposes two fundamental parameters of the World: fine-structure constant α and the quantity Q which is the dimensionless value of the fifth coordinate, and three fundamental physical units: basic unit of momentum, energy density, and energy flux density. WUM suggests that all time-dependent parameters of the World are inter- connected and in fact dependent on Q. We recommend adding the quantity Q to the list of the CODATA-recommended values. 展开更多
关键词 5D World-Universe model Medium of the World Mass-Varying Neutrinos Dineutrinos Bose- Einstein Condensates Far-Infrared Background Radiation Time-Varying Parameters of the World
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Spectra of the Energy Operator of Four-Electron Systems in the Impurity Hubbard Model. Triplet State 被引量:1
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作者 S. M. Tashpulatov R. T. Parmanova 《Journal of Applied Mathematics and Physics》 2021年第11期2776-2795,共20页
We consider the energy operator of four-electron systems in an impurity Hubbard model and investigated the structure of essential spectra and discrete spectrum of the system in the first triplet state in a one-dimensi... We consider the energy operator of four-electron systems in an impurity Hubbard model and investigated the structure of essential spectra and discrete spectrum of the system in the first triplet state in a one-dimensional lattice. For investigation the structure of essential spectra and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model, for which the momentum representation is convenient. In addition, we used the tensor products of Hilbert spaces and tensor products of operators in Hilbert spaces and described the structure of essential spectrum and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model. The investigations show that there are such cases: 1) the essential spectrum of the system consists of the union of no more than eight segments, and the discrete spectrum of the system consists of no more than three eigenvalues;2) the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues;3) the essential spectrum of the system consists of the union of no more than three segments, and the discrete spectrum of the system is the empty set. Consequently, the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues. 展开更多
关键词 Hubbard model Essential Spectrum Discrete Spectrum Four Electron Systems Quintet State Triplet State Singlet State SPECTRA
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Structure of Essential Spectra and Discrete Spectrum of the Energy Operator of Six-Electron Systems in the Hubbard Model. First Quintet and First Singlet States
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作者 S. M. Tashpulatov 《Journal of Applied Mathematics and Physics》 2022年第11期3424-3461,共38页
We consider the energy operator of six-electron systems in the Hubbard model and investigate the structure of essential spectra and discrete spectrum of the system in the first quintet and first singlet states in the ... We consider the energy operator of six-electron systems in the Hubbard model and investigate the structure of essential spectra and discrete spectrum of the system in the first quintet and first singlet states in the v-dimensional lattice. 展开更多
关键词 Hubbard model Essential Spectrum Discrete Spectrum Six Electron Systems Octet State Singlet State Quintet State
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Four-Electron Systems in the Impurity Hubbard Model. Second Triplet State. Spectra of the System in the ν-Dimensional Lattice Zν
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作者 S. M. Tashpulatov R. T. Parmanova 《Journal of Applied Mathematics and Physics》 2023年第11期3393-3427,共35页
We consider an energy operator of four-electron system in the Impurity Hubbard model with a coupling between nearest-neighbors. The spectrum of the systems in the second triplet state in a ν-dimensional lattice is in... We consider an energy operator of four-electron system in the Impurity Hubbard model with a coupling between nearest-neighbors. The spectrum of the systems in the second triplet state in a ν-dimensional lattice is investigated. For investigation the structure of essential spectra and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model, for which the momentum representation is convenient. In addition, we used the tensor products of Hilbert spaces and tensor products of operators in Hilbert spaces and described the structure of essential spectrum and discrete spectrum of the energy operator of four-electron systems in an impurity Hubbard model for the second triplet state of the system. The investigations show that the essential spectrum of the system consists of the union of no more than sixteen segments, and the discrete spectrum of the system consists of no more than eleven eigenvalues. 展开更多
关键词 Spectra of Four-Electron System Bound State Anti-Bound State Impurity Hubbard model Quintet State Singlet State Triplet State
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From the Hubble Constant to the Black Hole Model. Universe Expansion with Matter Creation and a New Perspective on Dark Energy Observations
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作者 Paolo Christillin 《Journal of Modern Physics》 2023年第11期1452-1457,共6页
Comparison of the Hubble parameter with cosmological quantities strongly supports the black hole model for the description of the Universe evolution. Such evolution requires matter creation and has implications for wh... Comparison of the Hubble parameter with cosmological quantities strongly supports the black hole model for the description of the Universe evolution. Such evolution requires matter creation and has implications for what is currently referred to as “dark energy” and the “cosmological constant”. 展开更多
关键词 Hubble Parameter Universe Expansion Black Hole model Matter Creation Gravitational Self Energy Dark Energy
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基于Hybrid Model的浙江省太阳总辐射估算及其时空分布特征
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作者 顾婷婷 潘娅英 张加易 《气象科学》 2025年第2期176-181,共6页
利用浙江省两个辐射站的观测资料,对地表太阳辐射模型Hybrid Model在浙江省的适用性进行评估分析。在此基础上,利用Hybrid Model重建浙江省71个站点1971—2020年的地表太阳辐射日数据集,并分析其时空变化特征。结果表明:Hybrid Model模... 利用浙江省两个辐射站的观测资料,对地表太阳辐射模型Hybrid Model在浙江省的适用性进行评估分析。在此基础上,利用Hybrid Model重建浙江省71个站点1971—2020年的地表太阳辐射日数据集,并分析其时空变化特征。结果表明:Hybrid Model模拟效果良好,和A-P模型计算结果进行对比,杭州站的平均误差、均方根误差、平均绝对百分比误差分别为2.01 MJ·m^(-2)、2.69 MJ·m^(-2)和18.02%,而洪家站的平均误差、均方根误差、平均绝对百分比误差分别为1.41 MJ·m^(-2)、1.85 MJ·m^(-2)和11.56%,误差均低于A-P模型,且Hybrid Model在各月模拟的误差波动较小。浙江省近50 a平均地表总辐射在3733~5060 MJ·m^(-2),高值区主要位于浙北平原及滨海岛屿地区。1971—2020年浙江省太阳总辐射呈明显减少的趋势,气候倾向率为-72 MJ·m^(-2)·(10 a)^(-1),并在1980s初和2000年中期发生了突变减少。 展开更多
关键词 Hybrid model 太阳总辐射 误差分析 时空分布
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空间非均匀TOPMODEL与陆面模式SSiB4的耦合及流域水文模拟
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作者 王倩 丹利 邓慧平 《气候与环境研究》 北大核心 2025年第3期311-321,共11页
为了寻求合理简化的流域地形指数水文模型TOPMODEL(Topographic Index model)用于大尺度的陆面模式,推导了土壤表层饱和导水率k0、衰减因子f和地下水补给速率R空间都可变的扩展的TOPMODEL,并将f空间非均匀分布的TOPMODEL与陆面模式SSiB... 为了寻求合理简化的流域地形指数水文模型TOPMODEL(Topographic Index model)用于大尺度的陆面模式,推导了土壤表层饱和导水率k0、衰减因子f和地下水补给速率R空间都可变的扩展的TOPMODEL,并将f空间非均匀分布的TOPMODEL与陆面模式SSiB4耦合(SSiB4/GTOP)。通过耦合模型在f空间非均匀条件下进行实际流域的水文模拟,分析f空间非均匀对流域土壤湿度、蒸散发、地表径流、基流和总径流的影响。主要结论有:(1)k0和R的空间变化并不改变经典TOPMODEL原有关系式,只要定义新的地形指数,k0和R空间非均匀TOPMODEL与空间均匀的TOPMODEL并无区别;(2) f空间变化条件下由于局地的地下水埋深还与局地的f值有关,地形指数相同的区域具有水文相似性这一结论不再成立;(3)与f空间均匀的模拟结果相比较,f随海拔高度h i增加而线性减小使模拟的流域土壤湿度、地表径流和流域蒸散减小但使基流和总径流增加;(4) f空间非均匀对流域水文模拟结果有影响,但其影响明显小于流域地形因子的影响。 展开更多
关键词 空间非均匀性 扩展的TOPmodel推导 耦合模型SSiB4/GTOP 流域水文模拟 f空间非均匀影响
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基于Modelica-LSTM双驱动的数字孪生机床热误差补偿模型构建
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作者 孙丽 王诗灏 +3 位作者 姜锋 关咏臻 徐家淳 刘荣玺 《制造技术与机床》 北大核心 2025年第10期205-213,共9页
针对数控机床在高速、高负载运行中因热变形导致的热误差问题,提出一种基于Modelica多领域建模与长短期记忆网络(long short-term memory,LSTM)联合驱动的热误差补偿方法。通过Modelica构建机床机械、电气、热力学多物理场耦合的高保真... 针对数控机床在高速、高负载运行中因热变形导致的热误差问题,提出一种基于Modelica多领域建模与长短期记忆网络(long short-term memory,LSTM)联合驱动的热误差补偿方法。通过Modelica构建机床机械、电气、热力学多物理场耦合的高保真数字孪生模型,结合LSTM对机理模型未覆盖的非线性动态误差进行数据驱动补偿。实验以五轴数控加工中心DMG MORI DMU 50为对象,在预热、阶梯加载及扰动工况下采集温度、振动和热误差数据,验证模型性能。结果表明,Modelica-LSTM双驱动模型相较于单一Modelica机理模型,均方根误差降低51.2%,补偿后误差波动幅度减少72%,在高温及动态工况下显著提升预测精度。该方法为高精密机床热误差补偿提供了物理与数据协同驱动的有效解决方案。 展开更多
关键词 数控机床 热误差补偿 modelICA 长短期记忆网络 多领域建模 数字孪生
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基于24Model的动火作业事故致因文本挖掘 被引量:1
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作者 牛茂辉 李威君 +1 位作者 刘音 王璐 《中国安全科学学报》 北大核心 2025年第3期151-158,共8页
为探究工业动火作业事故的根源,提出一种基于“2-4”模型(24Model)的文本挖掘方法。首先,收集整理220篇动火作业事故报告,并作为数据集,构建基于来自变换器的双向编码器表征量(BERT)的24Model分类器,使用预训练模型训练和评估事故报告... 为探究工业动火作业事故的根源,提出一种基于“2-4”模型(24Model)的文本挖掘方法。首先,收集整理220篇动火作业事故报告,并作为数据集,构建基于来自变换器的双向编码器表征量(BERT)的24Model分类器,使用预训练模型训练和评估事故报告数据集,构建分类模型;然后,通过基于BERT的关键字提取算法(KeyBERT)和词频-逆文档频率(TF-IDF)算法的组合权重,结合24Model框架,建立动火作业事故文本关键词指标体系;最后,通过文本挖掘关键词之间的网络共现关系,分析得到事故致因之间的相互关联。结果显示,基于BERT的24Model分类器模型能够系统准确地判定动火作业事故致因类别,通过组合权重筛选得到4个层级关键词指标体系,其中安全管理体系的权重最大,结合共现网络分析得到动火作业事故的7项关键致因。 展开更多
关键词 “2-4”模型(24model) 动火作业 事故致因 文本挖掘 指标体系
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Prognostic model for esophagogastric variceal rebleeding after endoscopic treatment in liver cirrhosis: A Chinese multicenter study 被引量:2
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作者 Jun-Yi Zhan Jie Chen +7 位作者 Jin-Zhong Yu Fei-Peng Xu Fei-Fei Xing De-Xin Wang Ming-Yan Yang Feng Xing Jian Wang Yong-Ping Mu 《World Journal of Gastroenterology》 SCIE CAS 2025年第2期85-101,共17页
BACKGROUND Rebleeding after recovery from esophagogastric variceal bleeding(EGVB)is a severe complication that is associated with high rates of both incidence and mortality.Despite its clinical importance,recognized p... BACKGROUND Rebleeding after recovery from esophagogastric variceal bleeding(EGVB)is a severe complication that is associated with high rates of both incidence and mortality.Despite its clinical importance,recognized prognostic models that can effectively predict esophagogastric variceal rebleeding in patients with liver cirrhosis are lacking.AIM To construct and externally validate a reliable prognostic model for predicting the occurrence of esophagogastric variceal rebleeding.METHODS This study included 477 EGVB patients across 2 cohorts:The derivation cohort(n=322)and the validation cohort(n=155).The primary outcome was rebleeding events within 1 year.The least absolute shrinkage and selection operator was applied for predictor selection,and multivariate Cox regression analysis was used to construct the prognostic model.Internal validation was performed with bootstrap resampling.We assessed the discrimination,calibration and accuracy of the model,and performed patient risk stratification.RESULTS Six predictors,including albumin and aspartate aminotransferase concentrations,white blood cell count,and the presence of ascites,portal vein thrombosis,and bleeding signs,were selected for the rebleeding event prediction following endoscopic treatment(REPET)model.In predicting rebleeding within 1 year,the REPET model ex-hibited a concordance index of 0.775 and a Brier score of 0.143 in the derivation cohort,alongside 0.862 and 0.127 in the validation cohort.Furthermore,the REPET model revealed a significant difference in rebleeding rates(P<0.01)between low-risk patients and intermediate-to high-risk patients in both cohorts.CONCLUSION We constructed and validated a new prognostic model for variceal rebleeding with excellent predictive per-formance,which will improve the clinical management of rebleeding in EGVB patients. 展开更多
关键词 Esophagogastric variceal bleeding Variceal rebleeding Liver cirrhosis Prognostic model Risk stratification Secondary prophylaxis
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Landslide Susceptibility Mapping Using RBFN-Based Ensemble Machine Learning Models 被引量:1
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作者 Duc-Dam Nguyen Nguyen Viet Tiep +5 位作者 Quynh-Anh Thi Bui Hiep Van Le Indra Prakash Romulus Costache Manish Pandey Binh Thai Pham 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期467-500,共34页
This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble lear... This study was aimed to prepare landslide susceptibility maps for the Pithoragarh district in Uttarakhand,India,using advanced ensemble models that combined Radial Basis Function Networks(RBFN)with three ensemble learning techniques:DAGGING(DG),MULTIBOOST(MB),and ADABOOST(AB).This combination resulted in three distinct ensemble models:DG-RBFN,MB-RBFN,and AB-RBFN.Additionally,a traditional weighted method,Information Value(IV),and a benchmark machine learning(ML)model,Multilayer Perceptron Neural Network(MLP),were employed for comparison and validation.The models were developed using ten landslide conditioning factors,which included slope,aspect,elevation,curvature,land cover,geomorphology,overburden depth,lithology,distance to rivers and distance to roads.These factors were instrumental in predicting the output variable,which was the probability of landslide occurrence.Statistical analysis of the models’performance indicated that the DG-RBFN model,with an Area Under ROC Curve(AUC)of 0.931,outperformed the other models.The AB-RBFN model achieved an AUC of 0.929,the MB-RBFN model had an AUC of 0.913,and the MLP model recorded an AUC of 0.926.These results suggest that the advanced ensemble ML model DG-RBFN was more accurate than traditional statistical model,single MLP model,and other ensemble models in preparing trustworthy landslide susceptibility maps,thereby enhancing land use planning and decision-making. 展开更多
关键词 Landslide susceptibility map spatial analysis ensemble modelling information values(IV)
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Reduced mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor contributes to neurodegeneration in a model of spinal and bulbar muscular atrophy pathology 被引量:1
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作者 Yiyang Qin Wenzhen Zhu +6 位作者 Tingting Guo Yiran Zhang Tingting Xing Peng Yin Shihua Li Xiao-Jiang Li Su Yang 《Neural Regeneration Research》 SCIE CAS 2025年第9期2655-2666,共12页
Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto r.The mutant androgen r... Spinal and bulbar muscular atrophy is a neurodegenerative disease caused by extended CAG trinucleotide repeats in the androgen receptor gene,which encodes a ligand-dependent transcription facto r.The mutant androgen receptor protein,characterized by polyglutamine expansion,is prone to misfolding and forms aggregates in both the nucleus and cytoplasm in the brain in spinal and bulbar muscular atrophy patients.These aggregates alter protein-protein interactions and compromise transcriptional activity.In this study,we reported that in both cultured N2a cells and mouse brain,mutant androgen receptor with polyglutamine expansion causes reduced expression of mesencephalic astrocyte-de rived neurotrophic factor.Overexpressio n of mesencephalic astrocyte-derived neurotrophic factor amelio rated the neurotoxicity of mutant androgen receptor through the inhibition of mutant androgen receptor aggregation.Conversely.knocking down endogenous mesencephalic astrocyte-derived neurotrophic factor in the mouse brain exacerbated neuronal damage and mutant androgen receptor aggregation.Our findings suggest that inhibition of mesencephalic astrocyte-derived neurotrophic factor expression by mutant androgen receptor is a potential mechanism underlying neurodegeneration in spinal and bulbar muscular atrophy. 展开更多
关键词 androgen receptor mesencephalic astrocyte-derived neurotrophic factor mouse model NEURODEGENERATION neuronal loss neurotrophic factor polyglutamine disease protein misfolding spinal and bulbar muscular atrophy transcription factor
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Solubility and Thermodynamic Modeling of 3⁃Nitro⁃1,2,4⁃triazole⁃5⁃one(NTO)in Different Binary Solvents 被引量:1
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作者 GUO Hao-qi YANG Yu-lin 《含能材料》 北大核心 2025年第3期295-303,共9页
Using a dynamic laser monitoring technique,the solubility of 3-nitro-1,2,4-triazole-5-one(NTO)was investigated in two different binary systems,namely hydroxylamine nitrate(HAN)-water and boric acid(HB)-water ranging f... Using a dynamic laser monitoring technique,the solubility of 3-nitro-1,2,4-triazole-5-one(NTO)was investigated in two different binary systems,namely hydroxylamine nitrate(HAN)-water and boric acid(HB)-water ranging from 278.15 K to 318.15 K.The solubility in each system was found to be positively correlated with temperature.Furthermore,solubility data were analyzed using four equations:the modified Apelblat equation,Van’t Hoff equation,λh equation and CNIBS/R-K equations,and they provided satisfactory results for both two systems.The average root-mean-square deviation(105RMSD)values for these models were less than 13.93.Calculations utilizing the Van’t Hoff equation and Gibbs equations facilitated the derivation of apparent thermodynamic properties of NTO dissolution in the two systems,including values for Gibbs free energy,enthalpy and entropy.The%ζ_(H)is larger than%ζ_(TS),and all the%ζ_(H)data are≥58.63%,indicating that the enthalpy make a greater contribution than entropy to theΔG_(soln)^(Θ). 展开更多
关键词 3-nitro-l 2 4-triazole-5-one(NTO) SOLUBILITY thermodynamic models apparent thermodynamic analysis
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Influence of different data selection criteria on internal geomagnetic field modeling 被引量:4
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作者 HongBo Yao JuYuan Xu +3 位作者 Yi Jiang Qing Yan Liang Yin PengFei Liu 《Earth and Planetary Physics》 2025年第3期541-549,共9页
Earth’s internal core and crustal magnetic fields,as measured by geomagnetic satellites like MSS-1(Macao Science Satellite-1)and Swarm,are vital for understanding core dynamics and tectonic evolution.To model these i... Earth’s internal core and crustal magnetic fields,as measured by geomagnetic satellites like MSS-1(Macao Science Satellite-1)and Swarm,are vital for understanding core dynamics and tectonic evolution.To model these internal magnetic fields accurately,data selection based on specific criteria is often employed to minimize the influence of rapidly changing current systems in the ionosphere and magnetosphere.However,the quantitative impact of various data selection criteria on internal geomagnetic field modeling is not well understood.This study aims to address this issue and provide a reference for constructing and applying geomagnetic field models.First,we collect the latest MSS-1 and Swarm satellite magnetic data and summarize widely used data selection criteria in geomagnetic field modeling.Second,we briefly describe the method to co-estimate the core,crustal,and large-scale magnetospheric fields using satellite magnetic data.Finally,we conduct a series of field modeling experiments with different data selection criteria to quantitatively estimate their influence.Our numerical experiments confirm that without selecting data from dark regions and geomagnetically quiet times,the resulting internal field differences at the Earth’s surface can range from tens to hundreds of nanotesla(nT).Additionally,we find that the uncertainties introduced into field models by different data selection criteria are significantly larger than the measurement accuracy of modern geomagnetic satellites.These uncertainties should be considered when utilizing constructed magnetic field models for scientific research and applications. 展开更多
关键词 Macao Science Satellite-1 SWARM geomagnetic field modeling data selection core field crustal field
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A multisource geomagnetic field model incorporating ocean circulation-induced magnetic field 被引量:5
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作者 HongBo Yao JuYuan Xu +2 位作者 Cong Yang ZhengYong Ren Keke Zhang 《Earth and Planetary Physics》 2025年第3期550-563,共14页
The movement of global ocean circulation in the Earth’s main magnetic field generates a measurable induced magnetic field(about 2 nT at geomagnetic satellite altitudes).However,this ocean circulation-induced magnetic... The movement of global ocean circulation in the Earth’s main magnetic field generates a measurable induced magnetic field(about 2 nT at geomagnetic satellite altitudes).However,this ocean circulation-induced magnetic field has not been previously estimated or incorporated into geomagnetic field models,potentially causing leakage into the core field model.Here,we present a method to account for the circulation-induced magnetic field during geomagnetic field modeling.First,a forward model of the circulation-induced magnetic field is constructed by numerically solving electromagnetic induction equations based on a realistic ocean circulation model.Then,this forward model is subtracted from the observed data.Finally,the core and lithospheric fields,magnetospheric and Earth’s mantle-induced fields,and the ocean tide-induced magnetic field are co-estimated.Applying our method to over 20 years of MSS-1,Swarm,CryoSat-2,and CHAMP satellite magnetic data,we derive a new multisource geomagnetic field model(MGFM).We find that incorporating a forward model of the circulation-induced magnetic field marginally improves the fit to the data.Furthermore,we demonstrate that neglecting the circulation-induced magnetic field in geomagnetic field modeling results in leakage into the core field model.The highlights of the MGFM model include:(i)a good agreement with the widely used CHAOS model series;(ii)the incorporation of magnetic fields induced by both ocean tides and circulation;and(iii)the suppression of leakage of the circulation-induced magnetic field into the core field model. 展开更多
关键词 Macao Science Satellite-1(MSS-1) geomagnetic field modeling ocean tides ocean circulation
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