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Sensor placement of long-term health monitoring for large bridges based on the real-time correction of finite element model

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Journal of Chongqing University 2013年第3期12卷 123-130页

作者：陈悦 ZHOU Jian-ting shen pei-wen College of Civil Engineering and Architecture Chongqing Jiaotong University Chongqing Construction Science Research Institute

The process of optimized placement of long-term health monitoring sensors for large bridges generally begins with finite element models, but there will arise great discrepancies between theoretically-calculated results and actual ***, rectified finite element models need to be rectified by virtue of model rectifying technology. Firstly, the result of construction monitoring and finished state load test is used to real-time modification of finite element model. Subsequently, an accurate finite element model is established. Secondly, the optimizing the layout of sensor with following orthogonality guarantees orthogonal property and linear independence for the measured data. Lastly, the effectiveness and feasibility of method in the paper is tested by real-time modifying finite element model and optimizing the layout of sensor for Nujiang Bridge.

关键词： large bridges health monitoring real-time correction optimal sensor placement

Remaining Life Prediction Method for Photovoltaic Modules Based on Two-Stage Wiener Process

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Energy Engineering 2025年第1期122卷 331-347页

作者： Jie Lin Hongchi shen Tingting pei Yan Wu School of Electrical Engineering and Information Engineering Lanzhou University of TechnologyLanzhou730050China

Photovoltaic (PV) modules, as essential components of solar power generation systems, significantly influence unitpower generation *** service life of these modules directly affects these costs. Over time, the performanceof PV modules gradually declines due to internal degradation and external environmental *** cumulativedegradation impacts the overall reliability of photovoltaic power generation. This study addresses the complexdegradation process of PV modules by developing a two-stage Wiener process model. This approach accountsfor the distinct phases of degradation resulting from module aging and environmental influences. A powerdegradation model based on the two-stage Wiener process is constructed to describe individual differences inmodule degradation processes. To estimate the model parameters, a combination of the Expectation-Maximization(EM) algorithm and the Bayesian method is employed. Furthermore, the Schwarz Information Criterion (SIC) isutilized to identify critical change points in PV module degradation trajectories. To validate the universality andeffectiveness of the proposed method, a comparative analysis is conducted against other established life predictiontechniques for PV modules.

关键词： Photovoltaic modules degradation stochastic processes lifetime prediction

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大跨度钢管混凝土拱桥施工阶段稳定性分析

重庆交通大学学报（自然科学版） 2010年第3期29卷 340-343页

作者：沈培文周水兴罗飞重庆交通大学土木建筑学院重庆400074 四川路桥集团大桥分公司四川成都610071

以新龙门大桥为工程依托,考虑钢管和混凝土的三向受力本构关系,利用ANSYS建立了空间有限元模型,从特征值屈曲、几何非线性失稳、几何材料双重非线性失稳3个方面分析了该桥整个施工阶段的稳定问题。结果表明:钢管混凝土拱桥在整个施工过... 详细信息

以新龙门大桥为工程依托,考虑钢管和混凝土的三向受力本构关系,利用ANSYS建立了空间有限元模型,从特征值屈曲、几何非线性失稳、几何材料双重非线性失稳3个方面分析了该桥整个施工阶段的稳定问题。结果表明:钢管混凝土拱桥在整个施工过程中受稳定性影响较大,稳定系数有不断下降的趋势,考虑双重非线性的稳定系数与特征值屈曲分析相比差别较大,最大可达30%。

关键词：钢管混凝土拱桥施工阶段稳定性本构关系屈曲非线性失稳

大采高工作面回采扰动对煤体结构影响的现场测试分析

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能源技术与管理 2020年第3期45卷 10-11,112页

作者：申培文山西晋城无烟煤矿业集团有限责任公司生产技术处山西晋城048006

以寺河煤矿留巷顺槽为工程背景,采用煤矿井下钻孔窥视研究方法,开展了回采扰动对煤体结构的影响现场测试分析。测试结果表明,随着回采时间加长,巷帮煤体的完整性降低。新掘巷道煤体裂隙率为22.7%,工作面回采过程中裂隙率为40.9%,工作面... 详细信息

以寺河煤矿留巷顺槽为工程背景,采用煤矿井下钻孔窥视研究方法,开展了回采扰动对煤体结构的影响现场测试分析。测试结果表明,随着回采时间加长,巷帮煤体的完整性降低。新掘巷道煤体裂隙率为22.7%,工作面回采过程中裂隙率为40.9%,工作面回采后裂隙率为58.5%。提出采取注浆加固技术提高围岩的自承能力和抗变形扰动能力,同时及时进行喷浆封闭防止围岩风化变形破碎。

关键词：大采高回采扰动煤体结构现场测试

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钢管混凝土拱桥安全评估方法研究及系统开发

重庆交通大学学报（自然科学版） 2011年第1期30卷 22-26页

作者：沈培文丁永灿周水兴陈悦重庆交通大学土木建筑学院重庆400074 广西交通职业技术学院广西南宁530023

针对现有养护规范中桥梁评估部分部件划分不全、权重计算粗糙等缺陷,建立了钢管混凝土拱桥递阶层次模型,并运用基于指数标度的层次分析法计算了部件权重;将部件的设计承载能力与缺损状况作为安全评估指标,结合结构层次分析模型与部件权... 详细信息

针对现有养护规范中桥梁评估部分部件划分不全、权重计算粗糙等缺陷,建立了钢管混凝土拱桥递阶层次模型,并运用基于指数标度的层次分析法计算了部件权重;将部件的设计承载能力与缺损状况作为安全评估指标,结合结构层次分析模型与部件权重,建立了完善的钢管混凝土拱桥安全评估指标体系;运用Visual Basic语言开发了钢管混凝土拱桥安全评估系统。将该评估系统运用于浙江省三门健跳大桥的安全评估中,结果表明:该系统能够准确、快速的评估结构的安全性,有效的减少了桥梁评估工作量。

关键词：钢管混凝土拱桥安全评估层次分析法指数标度承载能力缺损状况评估系统

Optimizing Fine-Tuning in Quantized Language Models:An In-Depth Analysis of Key Variables

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Computers, Materials & Continua 2025年第1期82卷 307-325页

作者： Ao shen Zhiquan Lai Dongsheng Li Xiaoyu Hu National Key Laboratory of Parallel and Distributed Computing National University of Defense TechnologyChangsha410073China Strategic Assessments and Consultation Institute Academy of Military ScienceBeijing100091China

Large-scale Language Models(LLMs)have achieved significant breakthroughs in Natural Language Processing(NLP),driven by the pre-training and fine-tuning *** this approach allows models to specialize in specific tasks with reduced training costs,the substantial memory requirements during fine-tuning present a barrier to broader ***-Efficient Fine-Tuning(PEFT)techniques,such as Low-Rank Adaptation(LoRA),and parameter quantization methods have emerged as solutions to address these challenges by optimizing memory usage and computational *** these,QLoRA,which combines PEFT and quantization,has demonstrated notable success in reducing memory footprints during fine-tuning,prompting the development of various QLoRA *** these advancements,the quantitative impact of key variables on the fine-tuning performance of quantized LLMs remains *** study presents a comprehensive analysis of these key variables,focusing on their influence across different layer types and depths within LLM *** investigation uncovers several critical findings:(1)Larger layers,such as MLP layers,can maintain performance despite reductions in adapter rank,while smaller layers,like self-attention layers,aremore sensitive to such changes;(2)The effectiveness of balancing factors depends more on specific values rather than layer type or depth;(3)In quantization-aware fine-tuning,larger layers can effectively utilize smaller adapters,whereas smaller layers struggle to do *** insights suggest that layer type is a more significant determinant of fine-tuning success than layer depth when optimizing quantized ***,for the same discount of trainable parameters,reducing the trainable parameters in a larger layer is more effective in preserving fine-tuning accuracy than in a smaller *** study provides valuable guidance for more efficient fine-tuning strategies and opens avenues for further research into optimizing LLM

关键词： Large-scale Language Model Parameter-Efficient Fine-Tuning parameter quantization key variable trainable parameters experimental analysis

Cerebral fat embolism following autologous fat injection in facial reconstruction:A case report

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World Journal of Clinical Cases 2025年第2期13卷 50-58页

作者： Xiu-Ying Chen Fa shen Chang Cheng Yu-Han Wang wen-Chao Cheng De-Zhi Yuan wen Huang Department of Neurology Chongqing Emergency Medical CenterChongqing University Central HospitalChongqing 400000China Department of Neurology Xinqiao HospitalThe Army Medical University(Third Military Medical University)Chongqing 400000China

BACKGROUND Autologous fat injection in facial reconstruction is a common cosmetic *** cerebral fat embolism(CFE)as a complication is rare,it carries serious health *** SUMMARY We present a case of a 29-year-old female patient who developed acute CFE following facial fat filling *** the surgery,the patient experienced symptoms including headache,nausea,vomiting,and difficulty breathing,which was followed by neurological symptoms such as slurred speech and left-sided *** physical examination and auxiliary investigations,including blood tests,head and neck computed tomography angiography,and cranial magnetic resonance diffusion-weighted imaging,were performed upon *** clinical diagnosis was acute cerebral embolism following facial fat filling *** included measures to improve cerebral circulation,dehydration for intracranial pressure reduction,nutritional support,and rehabilitation therapy for left limb *** patient showed a significant improvement in symptoms after 2 weeks of *** recovered left limb muscle strength to grade 5,had clear speech,and experienced complete relief of *** Our case highlights the potential occurrence of severe complications in patients undergoing fat injection in facial *** prevent these complications,plastic surgeons should enhance their professional knowledge and skills.

关键词： Cerebral fat embolism Mechanical thrombectomy Thrombolysis Steroid therapy Symptomatic treatment Case report

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关联维数在动静耦合破岩中的应用研究

湖南科技大学学报（自然科学版） 2010年第4期25卷 1-4页

作者：赵伏军陈才贤申培文李艳波湖南科技大学能源与安全工程学院湖南湘潭411201 六盘水师范学院资源与矿业工程系贵州六盘水553004

根据动静耦合加载切削破碎花岗岩试件的切削力信号,应用功率谱分析方法揭示了动静耦合切削破岩过程是混沌运动.在此基础上,采用关联维数定量表征了切削破岩反映出的信号特征.通过对动静耦合破岩分形特征的分析,得到了关联维数与动静耦... 详细信息

根据动静耦合加载切削破碎花岗岩试件的切削力信号,应用功率谱分析方法揭示了动静耦合切削破岩过程是混沌运动.在此基础上,采用关联维数定量表征了切削破岩反映出的信号特征.通过对动静耦合破岩分形特征的分析,得到了关联维数与动静耦合加载的关系,探讨了静压力与冲击能的组合对关联维数的影响.在不同动静耦合破岩过程中,关联维数与破岩比能的变化曲线极其相似.试验结果和理论分析表明:动静耦合破岩存在一个合理的静压力和冲击能的组合,可使破岩比能最小.关联维数可作为破岩比能改变的一个灵敏量,能简单、直观地辨识动静耦合参数在破岩中发挥作用的程度.为选取动静载荷的合理匹配值,有效提高破岩效果,提供了一种新的方法.

关键词：混沌动静耦合关联维数破岩比能

接枝法制备磺酸基碳微球及其催化缩合反应的应用

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现代化工 2017年第1期37卷 88-91,93页

作者：陈诗渊曾丹林许可吴洁沈康文裴阳王光辉武汉科技大学化工学院湖北省煤转化与新型炭材料重点实验室湖北武汉430081

以葡萄糖、烯丙基磺酸钠为原料,分别采用引发接枝、水热接枝2种方法成功制备了磺酸基碳微球,并通过SEM、FTIR、Boehm滴定对催化剂进行表征,结果表明,磺酸基碳微球表面存在着大量—SO3H、—COOH、—OH等活性官能团。同时考察了接枝法的... 详细信息

以葡萄糖、烯丙基磺酸钠为原料,分别采用引发接枝、水热接枝2种方法成功制备了磺酸基碳微球,并通过SEM、FTIR、Boehm滴定对催化剂进行表征,结果表明,磺酸基碳微球表面存在着大量—SO3H、—COOH、—OH等活性官能团。同时考察了接枝法的制备工艺条件,得出最佳引发接枝SO3H量为0.965 mmol/g和水热接枝SO3H量为0.946 mmol/g。将该磺酸基碳微球应用于催化合成环己酮乙二醇缩酮反应中,结果表明:在催化剂质量分数为15%,带水剂用量为15 m L,反应时间为3 h的条件下,产物最终的缩合收率可达92.9%,且引发接枝法制备的催化剂要优于水热接枝法制备的催化剂。

关键词：碳微球烯丙基磺酸钠接枝缩合反应