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Star Movement Is Not Predicted Two-Compartment Model of the Universe
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作者 Philip D. Houck 《Journal of Modern Physics》 2024年第11期1679-1689,共11页
A two-compartment model of the universe is proposed to further refine Albert Einstein’s insight into curvature of space and the energy tensor. The two compartments are energy contained by a shell prism. The model all... A two-compartment model of the universe is proposed to further refine Albert Einstein’s insight into curvature of space and the energy tensor. The two compartments are energy contained by a shell prism. The model allows for a non-unification of fundamental forces with gravity resulting from the curvature of a space-time prism. Carrier forces travel within the prism and particles emerge from the prism. Giving a thickness to the manifold negates infinity and will allow solutions at both microscopic and cosmic levels. Geometry is the link between quantum mechanics and general relativity. Negative entropy, as proposed by Erwin Schrödinger, gives order to particles and the cosmic. The source of this energy is in the shell of the containment vessel. The acceleration of the expansion of the universe occurred when energy within the container transformed into mass, warping the space-time container and causing an explosion of the container. Star movement is explained by the surface tension of the prism of space-time. 展开更多
关键词 two-compartment model Negative Entropy GEOMETRY
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Real-Time Analytical Solutions as Series Formulas and Heaviside off/on Switch Functions for Multiple Intermittent Intravenous Infusions in One- and Two-Compartment Models 被引量:2
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作者 Michalakis Savva 《Journal of Biosciences and Medicines》 2022年第1期150-189,共40页
Pharmacokinetic compartment models are the only models that can extract pharmacokinetic parameters from data collected in clinical studies but their estimates lack accuracy, explanations and physiological significance... Pharmacokinetic compartment models are the only models that can extract pharmacokinetic parameters from data collected in clinical studies but their estimates lack accuracy, explanations and physiological significance. The objective of this work was to develop particular solutions to drug concentration and AUC in the form of mathematical series and Heaviside functions for repetitive intermittent infusions in the one- and two-compartment models, as a function of dose number and total time using differential calculus. It was demonstrated that the central and peripheral compartment volumes determined from regression analysis of the aminoglycoside antibiotic Sisomicin concentration in plasma represent the actual physiological body fluid volumes accessible by the drug. The drug peak time and peak concentration in the peripheral compartment were also calculated as a function of dose number. It is also shown that the time of intercompartmental momentary distribution equilibrium can be used to determine the drug’s apparent volume of distribution within any dosing interval in multi-compartment models. These estimates were used to carry out simulations of plasma drug concentration with time in the one-compartment model. In conclusion, the two-compartment open mammillary pharmacokinetic model was fully explained for the aminoglycoside antibiotic sisomicin through the new concept of the apparent volume of distribution. 展开更多
关键词 PHARMACOKINETICS Intermittent Intravenous Infusion Multiple Doses Compartment models Heaviside Function Apparent Volume of Distribution
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A Reevaluation of Prazosin Pharmacokinetics in a Two-Compartment Model, the Apparent Volume of Distribution and Comparative Simulations in the One-Compartment Model 被引量:2
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作者 Michalakis Savva Xudong Yuan 《Journal of Biosciences and Medicines》 2022年第1期108-140,共33页
Published clinical data of Prazosin were reevaluated pharmacokinetically using explicit solutions to drug concentration as a function of total time for IV bolus injection, intermittent intravenous infusion and oral ro... Published clinical data of Prazosin were reevaluated pharmacokinetically using explicit solutions to drug concentration as a function of total time for IV bolus injection, intermittent intravenous infusion and oral routes of administration in an open two-compartment model. In a novel way, the apparent volume of distribution was estimated from a two-compartment model and found to be close to the total body water suggesting that Prazosin is distributed in all tissues both extracellularly and intracellularly. In addition, extracting the value of the apparent volume of distribution from a two-compartment model allowed comparative simulations in the one-compartment model. It is shown that dosage calculations of Prazosin intermittent infusion can be safely performed using the simpler one-compartment model equations. Lastly, several additional time-dependent pharmacokinetic parameters e.g., the peak time in the central and peripheral compartment and non-steady state and steady state peak concentration and AUC were determined using series equations for all three routes of administration, as a function of dose number and total time upon multiple drug administrations in the two-compartment model. It is also the first time that steady-state plasma drug concentration equations were derived in a two-compartment mammillary model. 展开更多
关键词 PRAZOSIN PHARMACOKINETICS Intravenous Bolus Intermittent Infusion Oral Dose Multiple Doses Compartment model Apparent Volume of Distribution
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A NEW TWO-COMPARTMENT MODEL OF PATIENT-ARTIFICIAL KIDNEY SYSTEM INCLUDING CSF COMPARTMENT
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作者 张凤宝 张国亮 +3 位作者 王绍亭 姜埃利 刘建勇 马腾骧 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1994年第4期44-52,共9页
A two-compartment model of patient-artificial kidney system consisting of a cerebrospinalfluid(CSF)and a body liquor compartments have been presented.With the model,the mechanism ofdisequilibrium syndrome occurred in ... A two-compartment model of patient-artificial kidney system consisting of a cerebrospinalfluid(CSF)and a body liquor compartments have been presented.With the model,the mechanism ofdisequilibrium syndrome occurred in a patient undergoing hemodialysis has been discussed to simulatethe CSF pressure transients.Urea,as an uretic toxin,was injected into dogs and in vivohemodialysis experiments have been performed under clinical conditions.The parameters in the sol-ution,G and K,have been determinde from experiments and are in good agreement with those re-ported under normal physiological conditions and in previous investigations. 展开更多
关键词 HEMODIALYSIS COMPARTMENT model CEREBROSPINAL fluid modelling
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Stationary distribution and extinction for a stochastic two-compartment model of B-cell chronic lymphocytic leukemia
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作者 Miaomiao Gao Daqing Jiang Xiangdan Wen 《International Journal of Biomathematics》 SCIE 2021年第8期141-156,共16页
In this paper,we study the dynamical behavior of a stochastic two-compartment model of B-cell chronic lymphocytic leukemia,which is perturbed by white noise.Firstly,by constructing suitable Lyapunov functions,we estab... In this paper,we study the dynamical behavior of a stochastic two-compartment model of B-cell chronic lymphocytic leukemia,which is perturbed by white noise.Firstly,by constructing suitable Lyapunov functions,we establish sufficient conditions for the existence of a unique ergodic stationary distribution.Then,conditions for extinction of the disease are derived.Furthermore,numerical simulations are presented for supporting the theoretical results.Our results show that large noise intensity may contribute to extinction of the disease. 展开更多
关键词 Stochastic two-compartment model B-cell chronic lymphocytic leukemia stationary distribution EXTINCTION
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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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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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An integrated method of data-driven and mechanism models for formation evaluation with logs 被引量:1
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作者 Meng-Lu Kang Jun Zhou +4 位作者 Juan Zhang Li-Zhi Xiao Guang-Zhi Liao Rong-Bo Shao Gang Luo 《Petroleum Science》 2025年第3期1110-1124,共15页
We propose an integrated method of data-driven and mechanism models for well logging formation evaluation,explicitly focusing on predicting reservoir parameters,such as porosity and water saturation.Accurately interpr... We propose an integrated method of data-driven and mechanism models for well logging formation evaluation,explicitly focusing on predicting reservoir parameters,such as porosity and water saturation.Accurately interpreting these parameters is crucial for effectively exploring and developing oil and gas.However,with the increasing complexity of geological conditions in this industry,there is a growing demand for improved accuracy in reservoir parameter prediction,leading to higher costs associated with manual interpretation.The conventional logging interpretation methods rely on empirical relationships between logging data and reservoir parameters,which suffer from low interpretation efficiency,intense subjectivity,and suitability for ideal conditions.The application of artificial intelligence in the interpretation of logging data provides a new solution to the problems existing in traditional methods.It is expected to improve the accuracy and efficiency of the interpretation.If large and high-quality datasets exist,data-driven models can reveal relationships of arbitrary complexity.Nevertheless,constructing sufficiently large logging datasets with reliable labels remains challenging,making it difficult to apply data-driven models effectively in logging data interpretation.Furthermore,data-driven models often act as“black boxes”without explaining their predictions or ensuring compliance with primary physical constraints.This paper proposes a machine learning method with strong physical constraints by integrating mechanism and data-driven models.Prior knowledge of logging data interpretation is embedded into machine learning regarding network structure,loss function,and optimization algorithm.We employ the Physically Informed Auto-Encoder(PIAE)to predict porosity and water saturation,which can be trained without labeled reservoir parameters using self-supervised learning techniques.This approach effectively achieves automated interpretation and facilitates generalization across diverse datasets. 展开更多
关键词 Well log Reservoir evaluation Label scarcity Mechanism model Data-driven model Physically informed model Self-supervised learning Machine learning
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Predictability Study of Weather and Climate Events Related to Artificial Intelligence Models 被引量:2
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作者 Mu MU Bo QIN Guokun DAI 《Advances in Atmospheric Sciences》 2025年第1期1-8,共8页
Conducting predictability studies is essential for tracing the source of forecast errors,which not only leads to the improvement of observation and forecasting systems,but also enhances the understanding of weather an... Conducting predictability studies is essential for tracing the source of forecast errors,which not only leads to the improvement of observation and forecasting systems,but also enhances the understanding of weather and climate phenomena.In the past few decades,dynamical numerical models have been the primary tools for predictability studies,achieving significant progress.Nowadays,with the advances in artificial intelligence(AI)techniques and accumulations of vast meteorological data,modeling weather and climate events using modern data-driven approaches is becoming trendy,where FourCastNet,Pangu-Weather,and GraphCast are successful pioneers.In this perspective article,we suggest AI models should not be limited to forecasting but be expanded to predictability studies,leveraging AI's advantages of high efficiency and self-contained optimization modules.To this end,we first remark that AI models should possess high simulation capability with fine spatiotemporal resolution for two kinds of predictability studies.AI models with high simulation capabilities comparable to numerical models can be considered to provide solutions to partial differential equations in a data-driven way.Then,we highlight several specific predictability issues with well-determined nonlinear optimization formulizations,which can be well-studied using AI models,holding significant scientific value.In addition,we advocate for the incorporation of AI models into the synergistic cycle of the cognition–observation–model paradigm.Comprehensive predictability studies have the potential to transform“big data”to“big and better data”and shift the focus from“AI for forecasts”to“AI for science”,ultimately advancing the development of the atmospheric and oceanic sciences. 展开更多
关键词 PREDICTABILITY artificial intelligence models simulation and forecasting nonlinear optimization cognition–observation–model paradigm
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Sensorless battery expansion estimation using electromechanical coupled models and machine learning 被引量:1
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作者 Xue Cai Caiping Zhang +4 位作者 Jue Chen Zeping Chen Linjing Zhang Dirk Uwe Sauer Weihan Li 《Journal of Energy Chemistry》 2025年第6期142-157,I0004,共17页
Developing sensorless techniques for estimating battery expansion is essential for effective mechanical state monitoring,improving the accuracy of digital twin simulation and abnormality detection.Therefore,this paper... Developing sensorless techniques for estimating battery expansion is essential for effective mechanical state monitoring,improving the accuracy of digital twin simulation and abnormality detection.Therefore,this paper presents a data-driven approach to expansion estimation using electromechanical coupled models with machine learning.The proposed method integrates reduced-order impedance models with data-driven mechanical models,coupling the electrochemical and mechanical states through the state of charge(SOC)and mechanical pressure within a state estimation framework.The coupling relationship was established through experimental insights into pressure-related impedance parameters and the nonlinear mechanical behavior with SOC and pressure.The data-driven model was interpreted by introducing a novel swelling coefficient defined by component stiffnesses to capture the nonlinear mechanical behavior across various mechanical constraints.Sensitivity analysis of the impedance model shows that updating model parameters with pressure can reduce the mean absolute error of simulated voltage by 20 mV and SOC estimation error by 2%.The results demonstrate the model's estimation capabilities,achieving a root mean square error of less than 1 kPa when the maximum expansion force is from 30 kPa to 120 kPa,outperforming calibrated stiffness models and other machine learning techniques.The model's robustness and generalizability are further supported by its effective handling of SOC estimation and pressure measurement errors.This work highlights the importance of the proposed framework in enhancing state estimation and fault diagnosis for lithium-ion batteries. 展开更多
关键词 Sensorless estimation Electromechanical coupling Impedance model Data-driven model Mechanical pressure
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A Multi-Level Semantic Constraint Approach for Highway Tunnel Scene Twin Modeling 被引量:1
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作者 LI Yufei XIE Yakun +3 位作者 CHEN Mingzhen ZHAO Yaoji TU Jiaxing HU Ya 《Journal of Geodesy and Geoinformation Science》 2025年第2期37-56,共20页
As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods ge... As a key node of modern transportation network,the informationization management of road tunnels is crucial to ensure the operation safety and traffic efficiency.However,the existing tunnel vehicle modeling methods generally have problems such as insufficient 3D scene description capability and low dynamic update efficiency,which are difficult to meet the demand of real-time accurate management.For this reason,this paper proposes a vehicle twin modeling method for road tunnels.This approach starts from the actual management needs,and supports multi-level dynamic modeling from vehicle type,size to color by constructing a vehicle model library that can be flexibly invoked;at the same time,semantic constraint rules with geometric layout,behavioral attributes,and spatial relationships are designed to ensure that the virtual model matches with the real model with a high degree of similarity;ultimately,the prototype system is constructed and the case region is selected for the case study,and the dynamic vehicle status in the tunnel is realized by integrating real-time monitoring data with semantic constraints for precise virtual-real mapping.Finally,the prototype system is constructed and case experiments are conducted in selected case areas,which are combined with real-time monitoring data to realize dynamic updating and three-dimensional visualization of vehicle states in tunnels.The experiments show that the proposed method can run smoothly with an average rendering efficiency of 17.70 ms while guaranteeing the modeling accuracy(composite similarity of 0.867),which significantly improves the real-time and intuitive tunnel management.The research results provide reliable technical support for intelligent operation and emergency response of road tunnels,and offer new ideas for digital twin modeling of complex scenes. 展开更多
关键词 highway tunnel twin modeling multi-level semantic constraints tunnel vehicles multidimensional modeling
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Large language models for robotics:Opportunities,challenges,and perspectives 被引量:3
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作者 Jiaqi Wang Enze Shi +7 位作者 Huawen Hu Chong Ma Yiheng Liu Xuhui Wang Yincheng Yao Xuan Liu Bao Ge Shu Zhang 《Journal of Automation and Intelligence》 2025年第1期52-64,共13页
Large language models(LLMs)have undergone significant expansion and have been increasingly integrated across various domains.Notably,in the realm of robot task planning,LLMs harness their advanced reasoning and langua... Large language models(LLMs)have undergone significant expansion and have been increasingly integrated across various domains.Notably,in the realm of robot task planning,LLMs harness their advanced reasoning and language comprehension capabilities to formulate precise and efficient action plans based on natural language instructions.However,for embodied tasks,where robots interact with complex environments,textonly LLMs often face challenges due to a lack of compatibility with robotic visual perception.This study provides a comprehensive overview of the emerging integration of LLMs and multimodal LLMs into various robotic tasks.Additionally,we propose a framework that utilizes multimodal GPT-4V to enhance embodied task planning through the combination of natural language instructions and robot visual perceptions.Our results,based on diverse datasets,indicate that GPT-4V effectively enhances robot performance in embodied tasks.This extensive survey and evaluation of LLMs and multimodal LLMs across a variety of robotic tasks enriches the understanding of LLM-centric embodied intelligence and provides forward-looking insights towards bridging the gap in Human-Robot-Environment interaction. 展开更多
关键词 Large language models ROBOTICS Generative AI Embodied intelligence
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Comparative study on the oblique water-entry of high-speed projectile based on rigid-body and elastic-plastic body model 被引量:1
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作者 Xiangyan Liu Xiaowei Cai +3 位作者 Zhengui Huang Yu Hou Jian Qin Zhihua Chen 《Defence Technology(防务技术)》 2025年第4期133-155,共23页
To examine the similarities and differences in the evolution of cavity,wetting and dynamics of a highspeed,oblique water-entry projectile with different positive angles of attack,a comparative analysis has been conduc... To examine the similarities and differences in the evolution of cavity,wetting and dynamics of a highspeed,oblique water-entry projectile with different positive angles of attack,a comparative analysis has been conducted based on the numerical results of two mathematical models,the rigid-body model and fluid-structure interaction model.In addition,the applicable scope of the above two methods,and the structural response characteristics of the projectile have also been investigated.Our results demonstrate that:(1) The impact loads and angular motion of the projectile of the rigid-body method are more likely to exhibit periodic variations due to the periodic tail slap,its range of positive angles of attack is about α<2°.(2) When the projectile undergone significant wetting,a strong coupling effect is observed among wetting,structural deformation,and projectile motion.With the applied projectile shape,it is observed that,when the projectile bends,the final wetting position is that of Part B(cylinder of body).With the occu rrence of this phenomenon,the projectile ballistics beco me completely unstable.(3) The force exerted on the lower surface of the projectile induced by wetting is the primary reason of the destabilization of the projectile traj ectory and structu ral deformation failure.Bending deformation is most likely to appear at the junction of Part C(cone of body) and Part D(tail).The safe angles of attack of the projectile stability are found to be about α≤2°. 展开更多
关键词 Fluid-structure interaction Rigid-body model Elastic-plastic model Structural deformation Impact loads Structural safety of projectile
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Dynamic intelligent prediction approach for landslide displacement based on biological growth models and CNN-LSTM 被引量:2
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作者 WANG Ziqian FANG Xiangwei +3 位作者 ZHANG Wengang WANG Luqi WANG Kai CHEN Chao 《Journal of Mountain Science》 2025年第1期71-88,共18页
Influenced by complex external factors,the displacement-time curve of reservoir landslides demonstrates both short-term and long-term diversity and dynamic complexity.It is difficult for existing methods,including Reg... Influenced by complex external factors,the displacement-time curve of reservoir landslides demonstrates both short-term and long-term diversity and dynamic complexity.It is difficult for existing methods,including Regression models and Neural network models,to perform multi-characteristic coupled displacement prediction because they fail to consider landslide creep characteristics.This paper integrates the creep characteristics of landslides with non-linear intelligent algorithms and proposes a dynamic intelligent landslide displacement prediction method based on a combination of the Biological Growth model(BG),Convolutional Neural Network(CNN),and Long ShortTerm Memory Network(LSTM).This prediction approach improves three different biological growth models,thereby effectively extracting landslide creep characteristic parameters.Simultaneously,it integrates external factors(rainfall and reservoir water level)to construct an internal and external comprehensive dataset for data augmentation,which is input into the improved CNN-LSTM model.Thereafter,harnessing the robust feature extraction capabilities and spatial translation invariance of CNN,the model autonomously captures short-term local fluctuation characteristics of landslide displacement,and combines LSTM's efficient handling of long-term nonlinear temporal data to improve prediction performance.An evaluation of the Liangshuijing landslide in the Three Gorges Reservoir Area indicates that BG-CNN-LSTM exhibits high prediction accuracy,excellent generalization capabilities when dealing with various types of landslides.The research provides an innovative approach to achieving the whole-process,realtime,high-precision displacement predictions for multicharacteristic coupled landslides. 展开更多
关键词 Reservoir landslides Displacement prediction CNN LSTM Biological growth model
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Fast full-color pathological imaging using Fourier ptychographic microscopy via closed-form model-based colorization 被引量:2
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作者 Yanqi Chen Jiurun Chen +4 位作者 Zhiping Wang Yuting Gao Yonghong He Yishi Shi An Pan 《Advanced Photonics Nexus》 2025年第2期7-16,共10页
Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution fo... Full-color imaging is essential in digital pathology for accurate tissue analysis.Utilizing advanced optical modulation and phase retrieval algorithms,Fourier ptychographic microscopy(FPM)offers a powerful solution for high-throughput digital pathology,combining high resolution,large field of view,and extended depth of field(DOF).However,the full-color capabilities of FPM are hindered by coherent color artifacts and reduced computational efficiency,which significantly limits its practical applications.Color-transferbased FPM(CFPM)has emerged as a potential solution,theoretically reducing both acquisition and reconstruction threefold time.Yet,existing methods fall short of achieving the desired reconstruction speed and colorization quality.In this study,we report a generalized dual-color-space constrained model for FPM colorization.This model provides a mathematical framework for model-based FPM colorization,enabling a closed-form solution without the need for redundant iterative calculations.Our approach,termed generalized CFPM(gCFPM),achieves colorization within seconds for megapixel-scale images,delivering superior colorization quality in terms of both colorfulness and sharpness,along with an extended DOF.Both simulations and experiments demonstrate that gCFPM surpasses state-of-the-art methods across all evaluated criteria.Our work offers a robust and comprehensive workflow for high-throughput full-color pathological imaging using FPM platforms,laying a solid foundation for future advancements in methodology and engineering. 展开更多
关键词 Fourier ptychographic microscopy color transfer dual-color-space constrained model
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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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Behavioral Animal Models and Neural-Circuit Framework of Depressive Disorder 被引量:1
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作者 Xiangyun Tian Scott J.Russo Long Li 《Neuroscience Bulletin》 2025年第2期272-288,共17页
Depressive disorder is a chronic,recurring,and potentially life-endangering neuropsychiatric disease.According to a report by the World Health Organization,the global population suffering from depression is experienci... Depressive disorder is a chronic,recurring,and potentially life-endangering neuropsychiatric disease.According to a report by the World Health Organization,the global population suffering from depression is experiencing a significant annual increase.Despite its prevalence and considerable impact on people,little is known about its pathogenesis.One major reason is the scarcity of reliable animal models due to the absence of consensus on the pathology and etiology of depression.Furthermore,the neural circuit mechanism of depression induced by various factors is particularly complex.Considering the variability in depressive behavior patterns and neurobiological mechanisms among different animal models of depression,a comparison between the neural circuits of depression induced by various factors is essential for its treatment.In this review,we mainly summarize the most widely used behavioral animal models and neural circuits under different triggers of depression,aiming to provide a theoretical basis for depression prevention. 展开更多
关键词 DEPRESSION Animal models STRESS Neural circuits
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