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Deformation energy of tectonic coal under hydrostatic conditions:A new calculation model based on critical state theory
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作者 Chenghao Wang Haisong Liu +2 位作者 Yuanping Cheng Liang Wang Jingyu Jiang 《International Journal of Mining Science and Technology》 2025年第1期87-100,共14页
The deformation energy(Wd)of soil-like tectonic coal is crucial for investigating the mechanism of coal and gas outbursts.Tectonic coal has a significant nonlinear constitutive relationship,which makes traditional ela... The deformation energy(Wd)of soil-like tectonic coal is crucial for investigating the mechanism of coal and gas outbursts.Tectonic coal has a significant nonlinear constitutive relationship,which makes traditional elastic-based models for computing Wdunsuitable.Inspired by critical state soil mechanics,this study theoretically established a new calculation model of Wdsuitable for the coal with nonlinear deformation characteristics.In the new model,the relationship between energy and stress no longer follows the square law(observed in traditional linear elastic models)but exhibits a power function,with the theoretical value of the power exponent ranging between 1 and 2.Hydrostatic cyclic loading and unloading experiments were conducted on four groups of tectonic coal samples and one group of intact coal samples.The results indicated that the relationship between Wdand stress for both intact and tectonic coal follows a power law.The exponents for intact and tectonic coal are close to 2 and 1,respectively.The stress-strain curve of intact coal exhibits small deformation and linear characteristics,whereas the stress-strain curves of tectonic coal show large deformation and nonlinear characteristics.The study specifically investigates the role of coal viscosity in the cyclic loading/unloading process.The downward bending in the unloading curves can be attributed to the time-dependent characteristics of coal,particularly its viscoelastic behavior.Based on experimental statistics,the calculation model of Wdwas further simplified.The simplified model involves only one unknown parameter,which is the power exponent between Wdand stress.The measured Wdof the coal samples increases with the number of load cycles.This phenomenon is attributed to coal's viscoelastic deformation.Within the same stress,the Wdof tectonic coal is an order of magnitude greater than that of intact coal.The calculation model of Wdproposed in this paper provides a new tool for studying the energy principle of coal and gas outbursts. 展开更多
关键词 Coal and gas outburst Tectonic coal Deformation energy Calculation model critical state soil mechanics
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The Application of O-AMAS Teaching Model Combined with PBL Teaching in the Clinical Teaching of Neurocritical Care Trainee Nurses
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作者 Chen Chen Jiao Mi 《Journal of Clinical and Nursing Research》 2025年第10期86-94,共9页
Objective:This study’s purpose is to explore the application of the O-AMAS teaching model combined with the PBL teaching method in the clinical teaching of neurocritical care trainee nurses.Methods:The nursing studen... Objective:This study’s purpose is to explore the application of the O-AMAS teaching model combined with the PBL teaching method in the clinical teaching of neurocritical care trainee nurses.Methods:The nursing students who were doing internship in neurocritical care from June 2024 to September 2024 were set as the control group,and the traditional one-on-one teaching mode was adopted;From October 2024 to January 2025,the nursing students were set as the observation group and the course teaching based on the O-AMAS teaching model combined with PBL teaching was implemented.Results:The theoretical examination scores,operational assessment scores,teaching satisfaction,autonomous learning ability and clinical evaluation thinking ability of the two groups of nursing students were observed.The score of the experimental group was significantly higher than that of the control group(all P<0.01).Conclusion:The application of the O-AMAS teaching model combined with PBL teaching in the clinical teaching of neurocritical care intern nursing students can improve the teaching effect and cultivate the autonomous learning ability and clinical evaluation thinking ability of nursing students. 展开更多
关键词 Clinical critical thinking Neurocritical care trainee nurse O-AMAS teaching model PBL teaching method Self-directed learning ability
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A Study of the Three English Translations of Shen Congwen’s Border Town Based on Reiss’s Translation Criticism Model
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作者 Yingzhi Qin 《Journal of Contemporary Educational Research》 2025年第6期264-271,共8页
To promote the global dissemination of Chinese culture,the translation of Chinese classic literature has garnered widespread attention in the translation field.Literary translation criticism plays an essential role in... To promote the global dissemination of Chinese culture,the translation of Chinese classic literature has garnered widespread attention in the translation field.Literary translation criticism plays an essential role in the development of translation endeavors.This paper will analyze three versions of English translations of Shen Congwen’s novella Border Town using Reiss’s translation criticism model and summarize their performance in terms of formal equivalence and aesthetic effect,linguistic components,and extra-linguistic components. 展开更多
关键词 Reiss’s translation criticism model Translation criticism TRANSLATION
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Research on the College English Teaching Mode Based on the Integration of Language Learning and Critical Thinking Ability Training
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作者 Hui Zhang 《Journal of Contemporary Educational Research》 2025年第5期115-121,共7页
Under the tide of economic globalization,college English teaching should not only focus on the improvement of language ability,but also on the cultivation of students’critical thinking ability.This paper takes the in... Under the tide of economic globalization,college English teaching should not only focus on the improvement of language ability,but also on the cultivation of students’critical thinking ability.This paper takes the integration of language learning and critical thinking ability as the breakthrough point,explores the college English teaching mode under the background of the integration of the two,analyzes the current situation and disadvantages of the separation of the two in the current teaching,and puts forward the integration path from the aspects of curriculum design,teacher training,evaluation system,and so on.With the help of activities such as creating real language situations,carrying out debates and critical reading,it helps students strengthen the improvement of logical analysis and critical thinking ability in their gradual learning,realize the coordinated development of language learning and critical thinking ability,and cultivate compound talents with both language literacy and critical thinking ability for the society. 展开更多
关键词 Language learning critical thinking ability INTEGRATION College English Teaching model
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Dynamic stability analysis of unsaturated slopes triggered by high gas pressure:Critical pressure threshold and progressive failure evolution
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作者 YAO Maohong CHEN Tielin +3 位作者 SONG Yin ZHANG Weifeng WANG Xiangfeng XING Xinfu 《Journal of Mountain Science》 2025年第8期2981-2995,共15页
Landslides triggered by high gas pressure represent a distinct geotechnical hazard,especially in scenarios without significant rainfall.Recent studies have revealed that high-pressure gas accumulation within slopes ca... Landslides triggered by high gas pressure represent a distinct geotechnical hazard,especially in scenarios without significant rainfall.Recent studies have revealed that high-pressure gas accumulation within slopes can be a dominant trigger for large-scale failures although the processes behind this remain not well understood.This study examines how unsaturated soil slopes fail under high gas pressure using a combination of laboratory experiments and numerical simulations.A key discovery is that gas pressure changes slope stability by redistributing pore fluids and altering effective stress,with distinct depthdependent effects.Moreover,a novel concept of critical stable gas pressure(P_(ac))is proposed as a practical threshold for stability assessment,which is depthdependent,with extreme values at shallow and intermediate depths,reflecting the interplay between gas diffusion and overburden resistance.This study advances the mechanistic understanding of gasinduced slope instability and offers actionable benchmarks for managing related risks in engineering projects including waste landfill management and shale gas operations. 展开更多
关键词 Coupled water-gas two-phase model Unsaturated slope stability critical stable gas pressure Progressive failure Pore fluid pressure
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Hysteresis-Loop Criticality in Disordered Ferromagnets–A Comprehensive Review of Computational Techniques
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作者 Djordje Spasojevic Sanja Janicevic +1 位作者 Svetislav Mijatovic Bosiljka Tadic 《Computer Modeling in Engineering & Sciences》 2025年第2期1021-1107,共87页
Disordered ferromagnets with a domain structure that exhibit a hysteresis loop when driven by the external magnetic field are essential materials for modern technological applications.Therefore,the understanding and p... Disordered ferromagnets with a domain structure that exhibit a hysteresis loop when driven by the external magnetic field are essential materials for modern technological applications.Therefore,the understanding and potential for controlling the hysteresis phenomenon in thesematerials,especially concerning the disorder-induced critical behavior on the hysteresis loop,have attracted significant experimental,theoretical,and numerical research efforts.We review the challenges of the numerical modeling of physical phenomena behind the hysteresis loop critical behavior in disordered ferromagnetic systems related to the non-equilibriumstochastic dynamics of domain walls driven by external fields.Specifically,using the extended Random Field Ising Model,we present different simulation approaches and advanced numerical techniques that adequately describe the hysteresis loop shapes and the collective nature of the magnetization fluctuations associated with the criticality of the hysteresis loop for different sample shapes and varied parameters of disorder and rate of change of the external field,as well as the influence of thermal fluctuations and demagnetizing fields.The studied examples demonstrate how these numerical approaches reveal newphysical insights,providing quantitativemeasures of pertinent variables extracted from the systems’simulated or experimentally measured Barkhausen noise signals.The described computational techniques using inherent scale-invariance can be applied to the analysis of various complex systems,both quantum and classical,exhibiting non-equilibrium dynamical critical point or self-organized criticality. 展开更多
关键词 Disordered ferromagnets hysteresis-loop criticality magnetization-reversal avalanches in simulations and experiments zero-temperature and thermal Random Field Ising model simulations computational techniques for multiparameter scaling analysis multifractal Barkhausen noise finite driving rates demagnetizing effects nonequilibrium critical dynamics
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The Role of Grid-Style Nursing Management Model in Critically Ill Patients 被引量:1
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作者 Xing Wang Li Zhang Shaohua Cai 《Journal of Clinical and Nursing Research》 2024年第8期163-168,共6页
Objective:This study aims to gain insight into the effects and potential advantages of the grid-style nursing management model in the care of critically ill patients.Methods:Eighty critically ill patients admitted to ... Objective:This study aims to gain insight into the effects and potential advantages of the grid-style nursing management model in the care of critically ill patients.Methods:Eighty critically ill patients admitted to our hospital between May 2020 and May 2021 were selected and randomly divided into the control group and the grid group,each with 40 patients.The control group implemented traditional nursing management,while the grid group adopted a grid-style nursing management model.The quality of care,quality of life,nursing satisfaction,and treatment adherence of the two groups were compared.Results:Compared with the control group,the grid group had significantly higher quality of care and quality of life(P<0.001);in terms of nursing satisfaction,the score of the grid group was 8.26±0.85,which was significantly higher than that of the control group(6.65±0.77)(P<0.001);90.00%(36 patients)of the grid group showed good treatment adherence,significantly higher than 70.00%(28 patients)of the control group(P<0.001).Conclusion:The implementation of the grid-style nursing management model in critically ill patients can significantly improve the quality of care,quality of life,and satisfaction of patients,and effectively promote patients’treatment adherence.These positive results provide strong support for the promotion and application of this model in clinical care. 展开更多
关键词 Grid-style Nursing management model critical illnesses
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Critical quality indicators of high-performance polyetherimide(ULTEM)over the MEX 3D printing key generic control parameters:Prospects for personalized equipment in the defense industry
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作者 Nectarios Vidakis Markos Petousis +6 位作者 Constantine David Nektarios K.Nasikas Dimitrios Sagris Nikolaos Mountakis Mariza Spiridaki Amalia Moutsopoulou Emmanuel Stratakis 《Defence Technology(防务技术)》 2025年第1期150-167,共18页
Additive Manufacturing(AM)can provide customized parts that conventional techniques fail to deliver.One important parameter in AM is the quality of the parts,as a result of the material extrusion 3D printing(3D-P)proc... Additive Manufacturing(AM)can provide customized parts that conventional techniques fail to deliver.One important parameter in AM is the quality of the parts,as a result of the material extrusion 3D printing(3D-P)procedure.This can be very important in defense-related applications,where optimum performance needs to be guaranteed.The quality of the Polyetherimide 3D-P specimens was examined by considering six control parameters,namely,infill percentage,layer height,deposition angle,travel speed,nozzle,and bed temperature.The quality indicators were the root mean square(Rq)and average(Ra)roughness,porosity,and the actual to nominal dimensional deviation.The examination was performed with optical profilometry,optical microscopy,and micro-computed tomography scanning.The Taguchi design of experiments was applied,with twenty-five runs,five levels for each control parameter,on five replicas.Two additional confirmation runs were conducted,to ensure reliability.Prediction equations were constructed to express the quality indicators in terms of the control parameters.Three modeling approaches were applied to the experimental data,to compare their efficiency,i.e.,Linear Regression Model(LRM),Reduced Quadratic Regression Model,and Quadratic Regression Model(QRM).QRM was the most accurate one,still the differences were not high even considering the simpler LRM model. 展开更多
关键词 Polyetherimide(PEI) Material extrusion(MEX) Three-dimensional printing(3D-P) critical quality indicators(CQIs) Quadratic regression model(QRM) Taguchi
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Data for critical infrastructure network modelling of natural hazard impacts:Needs and influence on model characteristics
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作者 Roman Schotten Evelyn Mühlhofer +3 位作者 Georgios-Alexandros Chatzistefanou Daniel Bachmann Albert S.Chen Elco E.Koks 《Resilient Cities and Structures》 2024年第1期55-65,共11页
Natural hazards impact interdependent infrastructure networks that keep modern society functional.While a va-riety of modelling approaches are available to represent critical infrastructure networks(CINs)on different ... Natural hazards impact interdependent infrastructure networks that keep modern society functional.While a va-riety of modelling approaches are available to represent critical infrastructure networks(CINs)on different scales and analyse the impacts of natural hazards,a recurring challenge for all modelling approaches is the availability and accessibility of sufficiently high-quality input and validation data.The resulting data gaps often require mod-ellers to assume specific technical parameters,functional relationships,and system behaviours.In other cases,expert knowledge from one sector is extrapolated to other sectoral structures or even cross-sectorally applied to fill data gaps.The uncertainties introduced by these assumptions and extrapolations and their influence on the quality of modelling outcomes are often poorly understood and difficult to capture,thereby eroding the reliability of these models to guide resilience enhancements.Additionally,ways of overcoming the data avail-ability challenges in CIN modelling,with respect to each modelling purpose,remain an open question.To address these challenges,a generic modelling workflow is derived from existing modelling approaches to examine model definition and validations,as well as the six CIN modelling stages,including mapping of infrastructure assets,quantification of dependencies,assessment of natural hazard impacts,response&recovery,quantification of CI services,and adaptation measures.The data requirements of each stage were systematically defined,and the literature on potential sources was reviewed to enhance data collection and raise awareness of potential pitfalls.The application of the derived workflow funnels into a framework to assess data availability challenges.This is shown through three case studies,taking into account their different modelling purposes:hazard hotspot assess-ments,hazard risk management,and sectoral adaptation.Based on the three model purpose types provided,a framework is suggested to explore the implications of data scarcity for certain data types,as well as their reasons and consequences for CIN model reliability.Finally,a discussion on overcoming the challenges of data scarcity is presented. 展开更多
关键词 critical infrastructure networks Impact modelling Data availability Natural hazards
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基于CRITIC组合赋权-正态云的山岭特长隧道洞口边坡失稳风险评价
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作者 张航 王星月 吕能超 《公路交通科技》 北大核心 2025年第7期170-182,共13页
【目标】建立山岭特长隧道洞口边坡失稳风险评价模型,以有效预测洞口边坡失稳风险等级,提升风险评估的科学性和准确性。【方法】提出了基于博弈论的CRITIC组合赋权-正态云评价模型。首先通过敏感性分析筛选关键影响因素,确定了由地形地... 【目标】建立山岭特长隧道洞口边坡失稳风险评价模型,以有效预测洞口边坡失稳风险等级,提升风险评估的科学性和准确性。【方法】提出了基于博弈论的CRITIC组合赋权-正态云评价模型。首先通过敏感性分析筛选关键影响因素,确定了由地形地貌、工程地质等多方面影响因素组成的评价指标体系。然后,分别使用优化的AHP法和CRITIC法计算指标的主客观权重,并基于博弈论对权重进行组合优化。最后采用正态云模型与模糊理论将专家打分结果与统计数据特性相结合,利用正向云发生器将定性指标转化为定量表达,构建标准云图以获取各指标的模糊隶属矩阵,通过多级模糊综合评判实现风险等级评估。结合云南省某公路项目特长隧道实际,对其洞口边坡失稳风险进行了施工前预评估。【结果】开挖工法、坡体结构、监控测量及岩体风化程度对洞口边坡失稳风险影响较大,洞口边坡失稳风险等级为Ⅱ级,属比较安全。该评估等级与模糊综合分析法、物元可拓法和风险矩阵法的对比验证结果一致,且与实际施工反馈相符,证明了该模型的有效性和适用性。【结论】模型兼顾决策者的主观意向和客观数据的潜在风险,量化定性指标,提高了指标权值及其隶属度的准确性,对隧道洞口边坡失稳风险等级判断及指导施工有一定的现实意义。 展开更多
关键词 隧道工程 风险评价 组合模型 山岭特长隧道 正态云模型 critic
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基于IAHP-CRITIC二维云模型的舰船电力系统韧性评价 被引量:1
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作者 胡涛 刘昊邦 +3 位作者 陈童 王宇江 李明贵 杜凯 《系统工程与电子技术》 北大核心 2025年第1期217-229,共13页
舰船电力系统是舰船正常运行的关键,具有高度的复杂性和模糊性,导致难以对其韧性做出准确、客观地评价。对此,基于对舰船电力系统主要任务的分析,对舰船电力系统韧性评价指标体系进行构建,采用区间层次分析法(interval analytic hierarc... 舰船电力系统是舰船正常运行的关键,具有高度的复杂性和模糊性,导致难以对其韧性做出准确、客观地评价。对此,基于对舰船电力系统主要任务的分析,对舰船电力系统韧性评价指标体系进行构建,采用区间层次分析法(interval analytic hierarchy process,IAHP)和层间相关性准则重要性法(criteria importance though intercrieria correlation,CRITIC)分别求解评价指标体系的主、客观权重,并运用改进博弈论方法确定组合权重,降低权重计算的主观性和随机性。结合二维云模型从防御能力和恢复能力两个维度对舰船电力系统韧性进行评价,更为全面、客观地反映舰船电力系统韧性。示例表明,所提方法能够有效解决舰船电力系统韧性评价中的随机性和不确定性问题,有利于得到更为准确、客观的评价结果。 展开更多
关键词 舰船电力系统 二维云模型 韧性评价 区间层次分析法 层间相关性准则重要性法
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Comparing gastrointestinal dysfunction score and acute gastrointestinal injury grade for predicting short-term mortality in critically ill patients 被引量:4
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作者 Chao Shen Xi Wang +3 位作者 Yi-Ying Xiao Jia-Ying Zhang Guo-Lian Xia Rong-Lin Jiang 《World Journal of Gastroenterology》 SCIE CAS 2024年第42期4523-4531,共9页
BACKGROUND The prognosis of critically ill patients is closely linked to their gastrointestinal(GI)function.The acute GI injury(AGI)grading system,established in 2012,is extensively utilized to evaluate GI dysfunction... BACKGROUND The prognosis of critically ill patients is closely linked to their gastrointestinal(GI)function.The acute GI injury(AGI)grading system,established in 2012,is extensively utilized to evaluate GI dysfunction and forecast outcomes in clinical settings.In 2021,the GI dysfunction score(GIDS)was developed,building on the AGI grading system,to enhance the accuracy of GI dysfunction severity assessment,improve prognostic predictions,reduce subjectivity,and increase reproducibility.AIM To compare the predictive capabilities of GIDS and the AGI grading system for 28-day mortality in critically ill patients.METHODS A retrospective study was conducted at the general intensive care unit(ICU)of a regional university hospital.All data were collected during the first week of ICU admission.The primary outcome was 28-day mortality.Multivariable logistic regression analyzed whether GIDS and AGI grade were independent risk factors for 28-day mortality.The predictive abilities of GIDS and AGI grade were compared using the receiver operating characteristic curve,with DeLong’s test assessing differences between the curves’areas.RESULTS The incidence of AGI in the first week of ICU admission was 92.13%.There were 85 deaths(47.75%)within 28 days of ICU admission.There was no initial 24-hour difference in GIDS between the non-survival and survival groups.Both GIDS(OR 2.01,95%CI:1.25-3.24;P=0.004)and AGI grade(OR 1.94,95%CI:1.12-3.38;P=0.019)were independent predictors of 28-day mortality.No significant difference was found between the predictive accuracy of GIDS and AGI grade for 28-day mortality during the first week of ICU admission(Z=-0.26,P=0.794).CONCLUSION GIDS within the first 24 hours was an unreliable predictor of 28-day mortality.The predictive accuracy for 28-day mortality from both systems during the first week was comparable. 展开更多
关键词 critical illness Gastrointestinal dysfunction Acute gastrointestinal injury Prognostic indicators Intensive care unit outcomes Mortality prediction Risk stratification Predictive modeling
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A Critical Model Construction of Knowledge Sharing Mechanism in Virtual Organization Based on Game Theoretic Perspective 被引量:9
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作者 LU Jinrong 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2015年第6期465-470,共6页
Virtual organization uses information technology to achieve a closer integration and better management of business relationships between internal and external parties. There are many emerging issues in virtual organiz... Virtual organization uses information technology to achieve a closer integration and better management of business relationships between internal and external parties. There are many emerging issues in virtual organization and one of them is knowl- edge sharing. Knowledge sharing that is the core of knowledge management plays a key role in virtual organization. However, game theoretic exploration about knowledge sharing mechanism based on virtual organization is seldom published, In this study, knowledge sharing mechanism in virtual organization enterprise is explored using game theories from two aspects based on the features of knowledge sharing in virtual organization enterprise. Fi- nally, the critical model of knowledge sharing mechanism in virtual organization also is presented based on the perspective of game analysis. 展开更多
关键词 game theoretic analysis knowledge sharing virtual organization critical model
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A unified critical state model for geomaterials with an application to tunnelling 被引量:4
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作者 Hai-Sui Yu Pei-Zhi Zhuang Pin-Qiang Mo 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2019年第3期464-480,共17页
This paper is prepared in honour of Professor E.T.Brown for his outstanding contributions to rock mechanics and geotechnical engineering and also for his personal influence on the first author’s research career in ge... This paper is prepared in honour of Professor E.T.Brown for his outstanding contributions to rock mechanics and geotechnical engineering and also for his personal influence on the first author’s research career in geomechanics and geotechnical engineering.As a result,we have picked a topic that reflects two key research areas in which Professor E.T.Brown has made seminal contributions over a long and distinguished career.These two areas are concerned with the application of the critical state concept to modelling geomaterials and the analysis of underground excavation or tunnelling in geomaterials.Partially due to Professor Brown’s influence,the first author has also been conducting research in these two areas over many years.In particular,this paper aims to describe briefly the development of a unified critical state model for geomaterials together with an application to cavity contraction problems and tunnelling in soils. 展开更多
关键词 critical state SOIL mechanics CONSTITUTIVE models Cavity CONTRACTION TUNNELLING in SOIL
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Critical behaviours and magnetic properties of three-dimensional bond and anisotropy dilution Blume-Capel model in the presence of an applied field 被引量:5
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作者 晏世雷 朱海霞 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第12期3026-3032,共7页
This paper studies the critical behaviours and magnetic properties of three-dimensional bond and anisotropy dilution Blume-Capel model (BCM) in the presence of an applied field within the effective field theory. The... This paper studies the critical behaviours and magnetic properties of three-dimensional bond and anisotropy dilution Blume-Capel model (BCM) in the presence of an applied field within the effective field theory. The trajectory of tricritical point, reentrant transitions and degenerate patterns of anisotropy are obtained both for the bond and the anisotropy dilutions. The global phase diagrams demonstrate unusually reentrant phenomena. The temperature dependences of magnetization curves undergo remarkable spin glass behaviour at low temperatures, and transform from ferromagnetism to paramagnetism at high temperature in applied fields. Temperature dependence of magnetic susceptibility curve is in qualitative agreement with experimental result. 展开更多
关键词 critical behaviours and magnetic properties Blume-Capel model bond and anisotropy dilutions applied field
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Thermo-mechanical constitutive modeling of unsaturated clays based on the critical state concepts 被引量:3
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作者 Saeed Tourchi Amir Hamidi 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2015年第2期193-198,共6页
A thermo-mechanical constitutive model for unsaturated clays is constructed based on the existingmodel for saturated clays originally proposed by the authors. The saturated clays model was formulatedin the framework o... A thermo-mechanical constitutive model for unsaturated clays is constructed based on the existingmodel for saturated clays originally proposed by the authors. The saturated clays model was formulatedin the framework of critical state soil mechanics and modified Cam-clay model. The existing model hasbeen generalized to simulate the experimentally observed behavior of unsaturated clays by introducingBishop's stress and suction as independent stress parameters and modifying the hardening rule and yieldcriterion to take into account the role of suction. Also, according to previous studies, an increase intemperature causes a reduction in specific volume. A reduction in suction (wetting) for a given confiningstress may induce an irreversible volumetric compression (collapse). Thus an increase in suction (drying)raises a specific volume i.e. the movement of normal consolidation line (NCL) to higher values of voidratio. However, some experimental data confirm the assumption that this reduction is dependent on thestress level of soil element. A generalized approach considering the effect of stress level on themagnitude of clays thermal dependency in compression plane is proposed in this study. The number ofmodeling parameters is kept to a minimum, and they all have clear physical interpretations, to facilitatethe usefulness of model for practical applications. A step-by-step procedure used for parameter calibrationis also described. The model is finally evaluated using a comprehensive set of experimental datafor the thermo-mechanical behavior of unsaturated soils.2015 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved. 展开更多
关键词 Constitutive model Unsaturated clays PLASTICITY Cam-clay critical state
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Acid deposition critical loads modeling for the simulation of sulfur exceedance and reduction in Guangdong, China 被引量:3
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作者 QIU Rongliang WANG Shizhong +3 位作者 QIU Hao WANG Xuemei LIAO Jin ZHANG Zhentian 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2009年第8期1108-1117,共10页
The current acid deposition critical loads in Guangdong, China were calculated using the PROFILE model with a 3 km × 3 km resolution. Calculations were carded out for critical loads of potential acidity, actual a... The current acid deposition critical loads in Guangdong, China were calculated using the PROFILE model with a 3 km × 3 km resolution. Calculations were carded out for critical loads of potential acidity, actual acidity, sulfur and nitrogen, with values in extents of 0-3.5, 0-14.0, 0-26.0 and 0-3.5 kmol/(hrnE.year), respectively. These values were comparable to previously reported results and reflected the influences of vegetation and soil characteristics on the soil acid buffering capacity. Simulations of SO2 emission and sulfur deposition in this study showed that sulfur deposition core areas mirrored SO2 emission centers. The prediction of sulfur deposition after 20% and 40% reduction of SO2 emission suggested that the reduction of area sources contributed greatly to the decrease of sulfur deposition. Thus, abatement of area source emissions could be the primary way to mitigate sulfur deposition in Guangdong to meet both the provincial and national regulations of air pollution control. 展开更多
关键词 acid deposition critical loads modelING SO2 reduction sulfur deposition exceedance and reduction
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Critical Exercise Price for American Floating Strike Lookback Option in a Mixed Jump-Diffusion Model 被引量:4
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作者 YANG Zhao-qiang 《Chinese Quarterly Journal of Mathematics》 2018年第3期240-259,共20页
This paper studies the critical exercise price of American floating strike lookback options under the mixed jump-diffusion model. By using It formula and Wick-It-Skorohod integral, a new market pricing model estab... This paper studies the critical exercise price of American floating strike lookback options under the mixed jump-diffusion model. By using It formula and Wick-It-Skorohod integral, a new market pricing model established under the environment of mixed jumpdiffusion fractional Brownian motion. The fundamental solutions of stochastic parabolic partial differential equations are estimated under the condition of Merton assumptions. The explicit integral representation of early exercise premium and the critical exercise price are also given, then the American floating strike lookback options factorization formula is obtained, the results is generalized the classical Black-Scholes market pricing model. 展开更多
关键词 MIXED JUMP-DIFFUSION fractional BROWNIAN motion Wick-Ito-Skorohod integral market pricing model option factorization critical exercise price
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Critical Behaviors in a Stochastic Local Limited One-Dimensional Rice-Pile Model 被引量:3
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作者 SUN Hong-Zhang TANG Zheng-Xin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第8期425-428,共4页
A stochastic local limited one-dimensional rice-pile model is numerically investigated. The distributions for avalanche sizes have a clear power-law behavior and it displays a simple finite size scaling. We obtain the... A stochastic local limited one-dimensional rice-pile model is numerically investigated. The distributions for avalanche sizes have a clear power-law behavior and it displays a simple finite size scaling. We obtain the avalanche exponents Ts= 1.54±0.10,βs = 2.17±0.10 and TT = 1.80±0.10, βT =1.46 ± 0.10. This self-organized critical model belongs to the same universality class with the Oslo rice-pile model studied by K. Christensen et al. [Phys. Rev. Lett. 77 (1996) 107], a rice-pile model studied by L.A.N. Amaral et al. [Phys. Rev. E 54 (1996) 4512], and a simple deterministic self-organized critical model studied by M.S. Vieira [Phys. Rev. E 61 (2000) 6056]. 展开更多
关键词 self-organized criticality rice-pile model finite size scaling universality class
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Advancing critical care recovery:The pivotal role of machine learning in early detection of intensive care unit-acquired weakness
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作者 Georges Khattar Elie Bou Sanayeh 《World Journal of Clinical Cases》 SCIE 2024年第21期4455-4459,共5页
This editorial explores the significant challenge of intensive care unit-acquiredweakness(ICU-AW),a prevalent condition affecting critically ill patients,characterizedby profound muscle weakness and complicating patie... This editorial explores the significant challenge of intensive care unit-acquiredweakness(ICU-AW),a prevalent condition affecting critically ill patients,characterizedby profound muscle weakness and complicating patient recovery.Highlightingthe paradox of modern medical advances,it emphasizes the urgent needfor early identification and intervention to mitigate ICU-AW's impact.Innovatively,the study by Wang et al is showcased for employing a multilayer perceptronneural network model,achieving high accuracy in predicting ICU-AWrisk.This advancement underscores the potential of neural network models inenhancing patient care but also calls for continued research to address limitationsand improve model applicability.The editorial advocates for the developmentand validation of sophisticated predictive tools,aiming for personalized carestrategies to reduce ICU-AW incidence and severity,ultimately improving patientoutcomes in critical care settings. 展开更多
关键词 critical illness myopathy critical illness polyneuropathy Early detection Intensive care unit-acquired weakness Neural network models Patient outcomes Personalized intervention strategies Predictive modeling
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