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Study on the Effects of Umbilical Acupuncture’s“Wind-Thunder Interaction Method”on Neuro-Vascular Regulatory Peptide Groups in SCH Patients with Liver Stagnation and Spleen Deficiency
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作者 Yongfeng Li Jialin Cheng +2 位作者 Hairong Wang Bihai Zhou Jianguo Mao 《Journal of Clinical and Nursing Research》 2025年第11期249-255,共7页
Objective:To evaluate the therapeutic efficacy of the umbilical acupuncture’s“Wind-Thunder Interaction Method”in treating schizophrenia(SCH)patients with liver stagnation and spleen deficiency.Methods:A total of 12... Objective:To evaluate the therapeutic efficacy of the umbilical acupuncture’s“Wind-Thunder Interaction Method”in treating schizophrenia(SCH)patients with liver stagnation and spleen deficiency.Methods:A total of 120 SCH patients with liver stagnation and spleen deficiency were selected and evenly divided by ball drawing.The umbilical acupuncture group received the“Wind-Thunder Interaction Method”,while the Western medicine group received pure Western medicine treatment.The outcomes were compared in terms of efficacy and other indicators.Results:The umbilical acupuncture group showed a higher total effective rate,a decrease in disease symptom scores,lower scores on the side effect rating scale,improved cognitive function scores,and excellent laboratory indicators,with p<0.05 between the groups.Conclusion:The“Wind-Thunder Interaction Method”of umbilical acupuncture demonstrated a relatively high effectiveness in treating SCH patients with liver stagnation and spleen deficiency,alleviating symptoms,reducing side effects,improving cognitive function,and facilitating the recovery of neuro-vascular regulatory peptide groups. 展开更多
关键词 Umbilical acupuncture’s“Wind-Thunder interaction method” SCH Liver stagnation and spleen deficiency Neuro-vascular regulatory peptide groups
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“Shamrock method”超声引导连续腰丛神经阻滞用于老年患者全膝关节置换术后镇痛的临床观察 被引量:7
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作者 公茂伟 孙永海 傅强 《中华老年多器官疾病杂志》 2015年第6期410-414,共5页
目的:评价“Shamrock method”超声引导联合刺激仪定位下连续腰丛神经阻滞与连续股神经阻滞对全膝关节置换术后镇痛的临床效果。方法采用开放、随机对照的研究方法,选择解放军总医院2014年6月至2014年12月择期行单侧全膝关节置换术的... 目的:评价“Shamrock method”超声引导联合刺激仪定位下连续腰丛神经阻滞与连续股神经阻滞对全膝关节置换术后镇痛的临床效果。方法采用开放、随机对照的研究方法,选择解放军总医院2014年6月至2014年12月择期行单侧全膝关节置换术的老年患者80例,年龄65~87岁,美国麻醉医师协会(ASA)分级Ⅱ~Ⅲ级,随机均分为连续腰丛神经阻滞组(L组)和连续股神经阻滞组(F组)。L组患者采用“Shamrock method”超声引导联合刺激仪定位下行腰丛神经阻滞,F组则采用超声引导联合刺激仪定位下行股神经阻滞,两组穿刺成功后均注入0.2%罗哌卡因30ml并留置导管,术后镇痛泵背景剂量为0.2%罗哌卡因5ml/h。记录术后6,12,24,48h时静息状态视觉模拟评分法(VAS)评分,术后24,48h膝关节功能锻炼时VAS评分和肌力评分;记录术后局麻药中毒、恶心呕吐和神经损伤等不良反应的发生情况。结果与L组相比较,F组术后各时点静息状态和功能锻炼VAS评分均明显增高(P<0.05),肌力评分两组间差异无统计学意义(P>0.05)。两组均未见局麻药中毒、神经损伤发生,且恶心呕吐等不良反应发生率两组间差异无统计学意义。结论“Shamrock method”超声引导联合刺激仪定位下连续腰丛神经阻滞对于老年患者全膝关节置换术后镇痛的临床效果优于连续股神经阻滞。 展开更多
关键词 Shamrock method 超声 腰骶丛 自主神经传导阻滞 股神经 老年人 关节成形术 置换 术后镇痛
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Clinical application and research of Shao's “three-acupoint and five-needling method” 被引量:1
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作者 张奥 严兴科 刘安国 《World Journal of Acupuncture-Moxibustion》 CSCD 2017年第1期74-80,共7页
Professor SHAO Jing-ming has obtained more significant effect during the clinical practice in treatment of wheezing diseases by adopting "three-acupoint and five-needling method" created by himself, and the effect h... Professor SHAO Jing-ming has obtained more significant effect during the clinical practice in treatment of wheezing diseases by adopting "three-acupoint and five-needling method" created by himself, and the effect has been widely recognized by doctors and patients. After decades of development, Shao's "three-acupoint and five-needling method" has become a therapy with complete theoretical system and a large number of clinical research achievements, and its application scope has been expanded. In this paper, the achievements of Shao's "three-acupoint and five-needling method" during clinical studies in the early, middle and current development stages and related problems were reviewed comprehensively. 展开更多
关键词 three-acupoint andmethod wheezing diseases clinicain the same wayfive-needling method Shao's needlingobservation different diseases be treated
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船舶电气专业基于“Callan Method”双语教学模式的研究与实践
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作者 唐卓贞 侯淑芳 龚旭 《南通航运职业技术学院学报》 2015年第2期122-124,共3页
文章提出了船舶电气专业开展"Callan Method"教学方法的必要性,并构建了基于"Callan Method"的双语教学模式,分析了试点教学效果,为船电专业双语教学模式的改革和创新提供了参考。
关键词 Callan method 船电专业 双语教学模式
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“Socratic Method”在外科护理学教学中的应用研究
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作者 吴丹 汪小燕 《九江学院学报(自然科学版)》 CAS 2014年第4期1-3,9,共4页
目的探讨"Socratic method"在外科护理学教学中的应用效果。方法选择九江学院2012级护理学专业专科6个班学生共229人作为研究对象,将1-3班学生116人作为实验组,部分授课内容采用"Socratic method"进行教学;将4-6班... 目的探讨"Socratic method"在外科护理学教学中的应用效果。方法选择九江学院2012级护理学专业专科6个班学生共229人作为研究对象,将1-3班学生116人作为实验组,部分授课内容采用"Socratic method"进行教学;将4-6班学生113人作为对照组,采用传统的教学方法进行教学。结果对照组总评成绩为(79.62±7.35)分,实验组总评成绩为(86.03±8.39)分,组间比较差异具有统计学意义(t=3.49,p<0.01)。结论 "Socratic method"符合护理临床专业课程的教学特点,有利于培养学生的综合能力,提高教学效果。 展开更多
关键词 Socratic method 外科护理 教学
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Application of the “Six-Step Teaching Method” in the Nursing Teaching of Obstetric Interns
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作者 Rui Liu Kun Yuan Yuanyuan Li 《Open Journal of Nursing》 2023年第9期615-623,共9页
Objective: The “six-step teaching method” is a teaching method, which is summarized based on practical experience. This study aimed to explore the effect of “six-step teaching method” in clinical teaching of ... Objective: The “six-step teaching method” is a teaching method, which is summarized based on practical experience. This study aimed to explore the effect of “six-step teaching method” in clinical teaching of obstetrics. Methods: A quasi-experimental study design was used, 30 nursing students who entered obstetrics practice from March 2022 to July 2022 were selected as the control group according to the order of time, and traditional teaching methods were adopted. From August to December 2022, 30 interns were selected as the experimental group, and the “six-step teaching method” was adopted. After 8 weeks of clinical practice, the assessment results and teaching effect satisfaction of the two groups were compared. Results: The scores of obstetrical specialty in the experimental group were higher than those in the control group, and the difference was statistically significant (P < 0.05);The evaluation of teaching methods, teaching quality, classroom atmosphere and individual observation ability, clinical thinking ability and nurse-patient communication ability of the experimental group were higher than those of the control group, and the differences were statistically significant (P Conclusion: “six-step teaching method” can effectively master the professional knowledge of obstetrics, stimulate the clinical thinking ability of interns, and improve the teaching effect and satisfaction. . 展开更多
关键词 “Six-Step Teaching method” Obstetrics Intern Nursing Education
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On“The Five-Step Method”in Teaching Junior English for China 被引量:1
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作者 黄金岩 《湖南工业大学学报(社会科学版)》 1997年第1期48-50,共3页
Junior English for China’ is based on the ’Five-Step’ teachingmethod: Revision, Presentation, Drilling, Practice, Consolidation. Each step has itsown particular methodology and requires the teacher to adopt a certa... Junior English for China’ is based on the ’Five-Step’ teachingmethod: Revision, Presentation, Drilling, Practice, Consolidation. Each step has itsown particular methodology and requires the teacher to adopt a certain role. Thispaper is a discussion of the "Five-Step Method". 展开更多
关键词 The Five-Step method JUNIOR English for China REVISION PRESENTATION DRILLING Practice CONSOLIDATION
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ANALYSIS OF THE LARGE DEFLECTION DYNAMIC PLASTIC RESPONSE OF SIMPLY-SUPPORTED CIRCULAR PLATES BY THE“MEMBRANE FACTOR METHOD” 被引量:2
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作者 Yu Tongxi (1) Chen Faliang (1) 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1990年第4期333-342,共10页
Based on energy equilibrium,a new procedure called the Membrane Factor Method is devel- oped to analyze the dynamic plastic response of plates with deflections in the range where both bending mo- ments and membrane fo... Based on energy equilibrium,a new procedure called the Membrane Factor Method is devel- oped to analyze the dynamic plastic response of plates with deflections in the range where both bending mo- ments and membrane forces are important.The final deflection of a simply -supported circular rigid-plastic plate loaded by a uniformly distributed impulse is obtained.In comparison with other approximate solutions, the present results are found to be simpler and in better agreement with the corresponding experimental values reoorded by Florence. 展开更多
关键词 dynamic plastic response of plates large deflection Membrane Factor method
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Scientific connotation of “treating different diseases with the same method” from the perspective of metabolic-immune dysregulation in inflammation-mediated carcinogenesis of digestive organs 被引量:1
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作者 Xia Ding Yunze Liu +2 位作者 Ruilin Wang Hong Shen Qi Wang 《Journal of Traditional Chinese Medical Sciences》 CAS 2023年第1期3-9,共7页
Inflammation-mediated carcinogenesis develops in the context of chronic inflammation and is a significant cause of cancer within the digestive system.In the chronic inflammation microenvironment,the metabolic activity... Inflammation-mediated carcinogenesis develops in the context of chronic inflammation and is a significant cause of cancer within the digestive system.In the chronic inflammation microenvironment,the metabolic activity of tissue cells undergoes extensive changes,which interfere with the normal function of immune cells.Dysregulation of cell metabolism and immune function has been identified as a key factor contributing to inflammation-mediated carcinogenesis within the major digestive organs,such as the stomach,liver,and colorectum.This metabolic-immune imbalance also corresponds to traditional Chinese medicine(TCM)theories of“yin-yang disharmony”and“disharmony between Ying-nutrients and Wei-defense.”The metabolic-immune imbalance has also been regarded as the key factor supporting“treatment of different diseases with the same method”,in which the same approach is adopted in the treatment of different conditions.In the TCM treatment process,it is necessary to first identify TCM patterns and then apply the corresponding TCM to correct the dysregulated metabolic and immune function,thereby blocking the progression from inflammation to malignancy.Our study findings deepen the TCM understanding of metabolic-immune dysregulation and the relationship between metabolic-immune dysregulation,pattern identification,and treatment method.They also provide new insights for the treatment of inflammation-mediated carcinogenesis in major digestive organs and help us further explore the scientific connotation of the TCM strategy of“treating different diseases with the same method”. 展开更多
关键词 Inflammation-mediated carcinogenesis Treating different diseases with the same method Metaboliceimmune regulation Metabolism Immunity Digestive system
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“Inverse Projection Method”Model in DEA to Measure Technological Progress
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作者 安景文 徐向阳 《International Journal of Mining Science and Technology》 SCIE EI 1997年第2期73-76,共4页
In view of the problems in measuring technological progress by DEA model, premias for DEA application is analyzed in this paper. An extended model of DEA is also raised for the cases running counter to the premisess. ... In view of the problems in measuring technological progress by DEA model, premias for DEA application is analyzed in this paper. An extended model of DEA is also raised for the cases running counter to the premisess. And precision about the results of the two models is analyzed. 展开更多
关键词 DEA TECHNOLOGICAL progress inverse-projection method
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New understanding of using“heart adjusting acupuncture method”to prevent and treat atherosclerotic cardiovascular disease
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作者 Yu Gao Guanhu Yang Chao An 《Journal of Traditional Chinese Medical Sciences》 CAS 2024年第4期389-394,共6页
This article explores the foundational research,Chinese medicine theories,and clinical applications of the“heart adjusting acupuncture method”developed by Professor Guanhu Yang to prevent and treat athero-sclerotic ... This article explores the foundational research,Chinese medicine theories,and clinical applications of the“heart adjusting acupuncture method”developed by Professor Guanhu Yang to prevent and treat athero-sclerotic cardiovascular disease(ASCVD).Professor Yang established this method based on experimental studies involving electroacupuncture along the horizontal umbilical line,which demonstrated a reduction in infarct area in the myocardial infarction mice model.This method was formulated using acupoints on the horizontal umbilical line:Daimai(GB 26),Tianshu(ST 25),and Daheng(SP 15).Clinical application has shown that it could effectively improve cardiac function and manage various cardiovascular conditions and proposed a new hypothesis for the treatment of myocardial infarction.Further research is required to determine if electroacupuncture stimulation at the site of myocardial infarction or during transportation can extend the critical treatment window,preserve myocardial tissue,and enhance reperfusion therapy prognosis.Professor Yang advocates that,when combined with active Western medicine treatments,the“heart adjusting acupuncture method”offers an effective measure to prevent and treat ASCVD. 展开更多
关键词 Atherosclerotic cardiovascular disease Nociceptor-induced conditioning Heart adjusting acupuncture method Clinical practice
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Reflection on ELT Methods and Principles from the Perspective of “Post-Method” Framework
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作者 骆园 《海外英语》 2019年第14期270-272,共3页
Over the past decades,the research in ELT methods has already experienced an ongoing transition from method-based pedagogy to post-method pedagogy.With regard to various method-based pedagogy,which is the best and app... Over the past decades,the research in ELT methods has already experienced an ongoing transition from method-based pedagogy to post-method pedagogy.With regard to various method-based pedagogy,which is the best and appropriate method for TEFL in China has been still a controversial and vital issue.By the reflection and critical analysis of my own experience as an EFL learner and of teaching methods and principles in ELT class as a college teacher,this paper mainly demonstrates there is no one so called‘best’or‘right’teaching methods for all from the perspective of Post-method framework which reflects a theoretical construct for teachers to effectively develop a systematic,and coherent pedagogy in their teaching context,aims to provide more instructive reference for ELT and English teachers’development in China. 展开更多
关键词 ELT methodS teaching PRINCIPLES POST-method PEDAGOGY REFLECTION
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A New Inversion-free Iterative Method for Solving the Nonlinear Matrix Equation and Its Application in Optimal Control
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作者 GAO Xiangyu XIE Weiwei ZHANG Lina 《应用数学》 北大核心 2026年第1期143-150,共8页
In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to ... In this paper,we consider the maximal positive definite solution of the nonlinear matrix equation.By using the idea of Algorithm 2.1 in ZHANG(2013),a new inversion-free method with a stepsize parameter is proposed to obtain the maximal positive definite solution of nonlinear matrix equation X+A^(*)X|^(-α)A=Q with the case 0<α≤1.Based on this method,a new iterative algorithm is developed,and its convergence proof is given.Finally,two numerical examples are provided to show the effectiveness of the proposed method. 展开更多
关键词 Nonlinear matrix equation Maximal positive definite solution Inversion-free iterative method Optimal control
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Crushing evolution in pebble bed based on a novel method:a crushable DEM study
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作者 Jian Wang Ming‑Zhun Lei +4 位作者 Ming‑Zong Liu Qi‑Gang Wu Zi‑Cong Cai Kai‑Song Wang Hai‑Shun Deng 《Nuclear Science and Techniques》 2026年第1期212-224,共13页
In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical m... In this paper,a novel method for investigating the particle-crushing behavior of breeding particles in a fusion blanket is proposed.The fractal theory and Weibull distribution are combined to establish a theoretical model,and its validity was verified using a simple impact test.A crushable discrete element method(DEM)framework is built based on the previously established theoretical model.The tensile strength,which considers the fractal theory,size effect,and Weibull variation,was assigned to each generated particle.The assigned strength is then used for crush detection by comparing it with its maximum tensile stress.Mass conservation is ensured by inserting a series of sub-particles whose total mass was equal to the quality loss.Based on the crushable DEM framework,a numerical simulation of the crushing behavior of a pebble bed with hollow cylindrical geometry under a uniaxial compression test was performed.The results of this investigation showed that the particle withstands the external load by contact and sliding at the beginning of the compression process,and the results confirmed that crushing can be considered an important method of resisting the increasing external load.A relatively regular particle arrangement aids in resisting the load and reduces the occurrence of particle crushing.However,a limit exists to the promotion of resistance.When the strain increases beyond this limit,the distribution of the crushing position tends to be isotropic over the entire pebble bed.The theoretical model and crushable DEM framework provide a new method for exploring the pebble bed in a fusion reactor,considering particle crushing. 展开更多
关键词 Crushing behavior Granular material Discrete element method Pebble bed Fractal theory
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A Deep Reinforcement Learning-Based Partitioning Method for Power System Parallel Restoration
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作者 Changcheng Li Weimeng Chang +1 位作者 Dahai Zhang Jinghan He 《Energy Engineering》 2026年第1期243-264,共22页
Effective partitioning is crucial for enabling parallel restoration of power systems after blackouts.This paper proposes a novel partitioning method based on deep reinforcement learning.First,the partitioning decision... Effective partitioning is crucial for enabling parallel restoration of power systems after blackouts.This paper proposes a novel partitioning method based on deep reinforcement learning.First,the partitioning decision process is formulated as a Markov decision process(MDP)model to maximize the modularity.Corresponding key partitioning constraints on parallel restoration are considered.Second,based on the partitioning objective and constraints,the reward function of the partitioning MDP model is set by adopting a relative deviation normalization scheme to reduce mutual interference between the reward and penalty in the reward function.The soft bonus scaling mechanism is introduced to mitigate overestimation caused by abrupt jumps in the reward.Then,the deep Q network method is applied to solve the partitioning MDP model and generate partitioning schemes.Two experience replay buffers are employed to speed up the training process of the method.Finally,case studies on the IEEE 39-bus test system demonstrate that the proposed method can generate a high-modularity partitioning result that meets all key partitioning constraints,thereby improving the parallelism and reliability of the restoration process.Moreover,simulation results demonstrate that an appropriate discount factor is crucial for ensuring both the convergence speed and the stability of the partitioning training. 展开更多
关键词 Partitioning method parallel restoration deep reinforcement learning experience replay buffer partitioning modularity
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An improved open-top dynamic chambers method for measuring the exchange fluxes of N_(2)O,NO and NH_(3) from farmland
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作者 Minhang Tan Yining Hu +6 位作者 Yifei Song Zixuan Huang Yujing Mu Junfeng Liu Chenglong Zhang Pengfei Liu Yuanyuan Zhang 《Journal of Environmental Sciences》 2026年第1期535-545,共11页
The application of nitrogen fertilizers in agricultural fields can lead to the release of nitrogen-containing gases(NCGs),such as NO_(x),NH_(3) and N_(2)O,which can significantly impact regional atmospheric environmen... The application of nitrogen fertilizers in agricultural fields can lead to the release of nitrogen-containing gases(NCGs),such as NO_(x),NH_(3) and N_(2)O,which can significantly impact regional atmospheric environment and con-tribute to global climate change.However,there remain considerable research gaps in the accurate measurement of NCGs emissions from agricultural fields,hindering the development of effective emission reduction strategies.We improved an open-top dynamic chambers(OTDCs)system and evaluated the performance by comparing the measured and given fluxes of the NCGs.The results showed that the measured fluxes of NO,N_(2)O and NH_(3)were 1%,2%and 7%lower than the given fluxes,respectively.For the determination of NH_(3) concentration,we employed a stripping coil-ion chromatograph(SC-IC)analytical technique,which demonstrated an absorption efficiency for atmospheric NH_(3) exceeding 96.1%across sampling durations of 6 to 60 min.In the summer maize season,we utilized the OTDCs system to measure the exchange fluxes of NO,NH_(3),and N_(2)O from the soil in the North China Plain.Substantial emissions of NO,NH_(3) and N_(2)O were recorded following fertilization,with peaks of 107,309,1239 ng N/(m^(2)·s),respectively.Notably,significant NCGs emissions were observed following sus-tained heavy rainfall one month after fertilization,particularly with NH_(3) peak being 4.5 times higher than that observed immediately after fertilization.Our results demonstrate that the OTDCs system accurately reflects the emission characteristics of soil NCGs and meets the requirements for long-term and continuous flux observation. 展开更多
关键词 Open-top dynamic chambers Nitrogen-containing gases Soil emissions North China Plain method evaluation
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Numerical Simulation of the Welding Deformation of Marine Thin Plates Based on a Temperature Gradient-thermal Strain Method
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作者 Lin Wang Yugang Miao +3 位作者 Zhenjian Zhuo Chunxiang Lin Benshun Zhang Duanfeng Han 《哈尔滨工程大学学报(英文版)》 2026年第1期122-135,共14页
Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The t... Marine thin plates are susceptible to welding deformation owing to their low structural stiffness.Therefore,the efficient and accurate prediction of welding deformation is essential for improving welding quality.The traditional thermal elastic-plastic finite element method(TEP-FEM)can accurately predict welding deformation.However,its efficiency is low because of the complex nonlinear transient computation,making it difficult to meet the needs of rapid engineering evaluation.To address this challenge,this study proposes an efficient prediction method for welding deformation in marine thin plate butt welds.This method is based on the coupled temperature gradient-thermal strain method(TG-TSM)that integrates inherent strain theory with a shell element finite element model.The proposed method first extracts the distribution pattern and characteristic value of welding-induced inherent strain through TEP-FEM analysis.This strain is then converted into the equivalent thermal load applied to the shell element model for rapid computation.The proposed method-particularly,the gradual temperature gradient-thermal strain method(GTG-TSM)-achieved improved computational efficiency and consistent precision.Furthermore,the proposed method required much less computation time than the traditional TEP-FEM.Thus,this study lays the foundation for future prediction of welding deformation in more complex marine thin plates. 展开更多
关键词 Marine thin plate Welding deformation Numerical simulation Temperature gradient-thermal strain method Shell element
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Precision and trueness of a method for determing antimony content in groundwater using hydride generation-atomic fluorescence spectrometry
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作者 Bing-bing Liu Lin Zhang Ke Li 《Journal of Groundwater Science and Engineering》 2026年第1期49-58,共10页
At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systema... At present,there is currently a lack of unified standard methods for the determination of antimony content in groundwater in China.The precision and trueness of related detection technologies have not yet been systematically and quantitatively evaluated,which limits the effective implementation of environmental monitoring.In response to this key technical gap,this study aimed to establish a standardized method for determining antimony in groundwater using Hydride Generation–Atomic Fluorescence Spectrometry(HG-AFS).Ten laboratories participated in inter-laboratory collaborative tests,and the statistical analysis of the test data was carried out in strict accordance with the technical specifications of GB/T 6379.2—2004 and GB/T 6379.4—2006.The consistency and outliers of the data were tested by Mandel's h and k statistics,the Grubbs test and the Cochran test,and the outliers were removed to optimize the data,thereby significantly improving the reliability and accuracy.Based on the optimized data,parameters such as the repeatability limit(r),reproducibility limit(R),and method bias value(δ)were determined,and the trueness of the method was statistically evaluated.At the same time,precision-function relationships were established,and all results met the requirements.The results show that the lower the antimony content,the lower the repeatability limit(r)and reproducibility limit(R),indicating that the measurement error mainly originates from the detection limit of the method and instrument sensitivity.Therefore,improving the instrument sensitivity and reducing the detection limit are the keys to controlling the analytical error and improving precision.This study provides reliable data support and a solid technical foundation for the establishment and evaluation of standardized methods for the determination of antimony content in groundwater. 展开更多
关键词 Mandel's h and k statistics Grubbs test Cochran test Repeatability limit Reproducibility limit method bias value
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Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations:A Review 被引量:5
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作者 Chao Zhang Shang-Xi Lai Hua-Ping Wang 《Structural Durability & Health Monitoring》 EI 2025年第1期25-54,共30页
Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters accordi... Modal parameters can accurately characterize the structural dynamic properties and assess the physical state of the structure.Therefore,it is particularly significant to identify the structural modal parameters according to the monitoring data information in the structural health monitoring(SHM)system,so as to provide a scientific basis for structural damage identification and dynamic model modification.In view of this,this paper reviews methods for identifying structural modal parameters under environmental excitation and briefly describes how to identify structural damages based on the derived modal parameters.The paper primarily introduces data-driven modal parameter recognition methods(e.g.,time-domain,frequency-domain,and time-frequency-domain methods,etc.),briefly describes damage identification methods based on the variations of modal parameters(e.g.,natural frequency,modal shapes,and curvature modal shapes,etc.)and modal validation methods(e.g.,Stability Diagram and Modal Assurance Criterion,etc.).The current status of the application of artificial intelligence(AI)methods in the direction of modal parameter recognition and damage identification is further discussed.Based on the pre-vious analysis,the main development trends of structural modal parameter recognition and damage identification methods are given to provide scientific references for the optimized design and functional upgrading of SHM systems. 展开更多
关键词 Structural health monitoring data information modal parameters damage identification AI method
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Study of the Transport Behavior of Multispherical Proppant in Intersecting Fracture Based on Discrete Element Method 被引量:1
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作者 Chengyong Peng JianshuWu +2 位作者 Mao Jiang Biao Yin Yishan Lou 《Energy Engineering》 EI 2025年第1期185-201,共17页
To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fract... To analyze the differences in the transport and distribution of different types of proppants and to address issues such as the short effective support of proppant and poor placement in hydraulically intersecting fractures,this study considered the combined impact of geological-engineering factors on conductivity.Using reservoir production parameters and the discrete elementmethod,multispherical proppants were constructed.Additionally,a 3D fracture model,based on the specified conditions of the L block,employed coupled(Computational Fluid Dynamics)CFD-DEM(Discrete ElementMethod)for joint simulations to quantitatively analyze the transport and placement patterns of multispherical proppants in intersecting fractures.Results indicate that turbulent kinetic energy is an intrinsic factor affecting proppant transport.Moreover,the efficiency of placement and migration distance of low-sphericity quartz sand constructed by the DEM in the main fracture are significantly reduced compared to spherical ceramic proppants,with a 27.7%decrease in the volume fraction of the fracture surface,subsequently affecting the placement concentration and damaging fracture conductivity.Compared to small-angle fractures,controlling artificial and natural fractures to expand at angles of 45°to 60°increases the effective support length by approximately 20.6%.During hydraulic fracturing of gas wells,ensuring the fracture support area and post-closure conductivity can be achieved by controlling the sphericity of proppants and adjusting the perforation direction to control the direction of artificial fractures. 展开更多
关键词 Hydraulic fracturing discrete element method PROPPANT SPHERICITY CFD-DEM
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