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基于Bootstrap-GA-ELM算法的清香型白酒发酵过程酒醅淀粉和水分含量区间预测模型
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作者 张贵宇 向星睿 +3 位作者 张磊 王怡博 严俊 张云龙 《现代食品科技》 北大核心 2026年第3期211-222,共12页
针对清香型白酒发酵过程酒醅淀粉和水分含量信息难以获取的困境,且传统点预测模型仅提供单一预测值而难以量化结果的可靠度的问题,提出一种发酵过程酒醅淀粉和水分含量区间预测模型。首先,从黄水理化参数和酒醅温度等易测潜在解释变量中... 针对清香型白酒发酵过程酒醅淀粉和水分含量信息难以获取的困境,且传统点预测模型仅提供单一预测值而难以量化结果的可靠度的问题,提出一种发酵过程酒醅淀粉和水分含量区间预测模型。首先,从黄水理化参数和酒醅温度等易测潜在解释变量中,通过相关系数、最小角回归(LARS)综合分析确定酒醅淀粉和水分预测模型的输入参数。其次,通过遗传算法(GA)优化极限学习机(ELM)的隐层权值和阈值,建立精度较高的酒醅淀粉和水分点预测模型。最后,通过4种不同自助法(Bootstrap)对点预测结果、系统误差以及随机误差进行估计,以此构建不同置信度下的酒醅淀粉和水分含量预测区间。结果表明,在99%置信度下,基于Residual Bootstrap方法建立的区间预测模型效果最好,在酒醅淀粉和水分测试集上,点预测的判定系数(R^(2))和均方根误差(RMSE)分别为0.9989、0.1091,0.9203、0.8021,预测区间的区间覆盖率(PICP)和平均预测区间宽度(MPIW)分别为100%、0.7280%,100%、4.3399%。该研究可对清香型白酒发酵过程酒醅淀粉和水分含量进行可靠预测,为白酒生产指导和发酵过程透明化提供参考。 展开更多
关键词 酒醅 淀粉 水分 黄水 相关性 点预测 区间预测 bootstrap方法
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A Cost-Effective Approach to Precisely Estimate Singlet-Triplet Energy Gaps in MR-TADF Molecules:Combining Delta Self-Consistent Field and Time-Dependent Density Functional Theory Methods
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作者 Qian Jina Dong Wang 《Chinese Journal of Chemical Physics》 2026年第1期41-50,I0021-I0032,I0042,共23页
As a novel class of purely organic fluores-cent materials,multiple resonance thermal-ly activated delayed fluorescence(MR-TADF)compounds hold significant promise for next-generation display technologies.The efficiency... As a novel class of purely organic fluores-cent materials,multiple resonance thermal-ly activated delayed fluorescence(MR-TADF)compounds hold significant promise for next-generation display technologies.The efficiency of exciton utilization and the overall performance of organic light-emit-ting devices are closely linked to the singlet-triplet energy gap(ΔE_(ST))of MR-TADF emitters.Identifying an economic and accu-rate theoretical approach to predictΔE_(ST)would be beneficial for high-throughput screening and facilitate the inverse design of MR-TADF molecules.In this study,we evaluated the S_(1)state energy(E(S_(1))),T_(1)state ener-gy(E(T_(1))),andΔE_(ST)using three different physical interpretations:adiabatic excitation ener-gy,vertical absorption energy,and vertical emission energy.We employed the time-depen-dent density functional theory(TDDFT)and delta self-consistent field(ΔSCF)methods to calculate E(S_(1)),E(T_(1)),andΔE_(ST)for 20 MR-TADF molecules reported in the literature.We compared these calculated values with experimental data obtained from fluorescence spec-troscopy at room-temperature(or 77 K)and phosphorescence spectroscopy conducted at 77 K.Our findings indicate that the vertical absorption energy at the S0 state minimum,deter-mined by theΔSCF method,accurately predicts the S_(1)state energy.Similarly,the vertical absorption energy at the S0 state minimum,calculated using the TDDFT method,effectively predicts the T_(1)state energy.TheΔE_(ST)derived from the difference between these two excita-tion energies exhibited the smallest mean absolute error of only 0.039 eV compared to the ex-perimental values.This combination represents the most accurate and cost-effective method reported to date for predicting theΔE_(ST)of MR-TADF molecules,and can be integrated into AI-driven inverse design workflows for new emitters. 展开更多
关键词 Organic light-emitting diode Multiple resonance thermally activated delayed fluorescence emitter Single-triplet energy gap Delta self-consistent field method Time-de-pendent density functional theory method
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Healthcare professionals’perspectives on disclosure of diagnosis and related issues in childhood cancer:A mixed methods systematic review
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作者 Run Xie Xiaoyan Huang +4 位作者 Yiran Du Ying Gu Qiongfang Kang Hongsheng Wang Daqian Zhu 《International Journal of Nursing Sciences》 2026年第1期96-104,I0006,共10页
Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of... Objectives This review aimed to systematically synthesize the available research on the disclosure of diagnosis and related issues in childhood cancer from the perspectives of healthcare professionals,with the goal of informing the optimization of disclosure processes and meeting the communication needs of affected families.Methods In accordance with the Joanna Briggs Institute(JBI)methodology for mixed methods systematic reviews,the convergent segregated approach was used in this review.Articles were retrieved from 11 databases,including PubMed,Web of Science,CINAHL,CENTRAL,Embase,Ovid/Medline,PsycINFO,PsycArticles,Scopus,ERIC,and China National Knowledge Infrastructure(CNKI).The quality of the selected articles was assessed using the Mixed Method Appraisal Tool(MMAT).The review protocol was registered on PROSPERO(CRD42024542746).Results A total of 21 studies from 10 countries were included.Their methodological quality was generally medium to high,with MMAT scores ranging from 60%to 100%.The synthesis yielded three core themes:1)the spectrum of professional and societal attitudes toward disclosure;2)the dynamic practices of navigating disclosure amid uncertainty,including timing and environment,stakeholders,and content of disclosure;and 3)factors influencing disclosure,including children’s,parental,healthcare professionals’,and socio-cultural factors.Conclusions This review synthesized the perspectives and experiences of healthcare professionals regarding disclosure in childhood cancer,highlighting the complexity and multidimensional nature of this process in clinical practice.Future research should further investigate the experiences and needs of children and their parents,explore cultural variations in disclosure practices,develop context-appropriate assessment tools,and construct multidimensional intervention strategies to enhance the humanistic care and professional effectiveness of the disclosure process. 展开更多
关键词 Communication CANCER DISCLOSURE Healthcare professionals Mixed methods PEDIATRIC Systematic review
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Subtitle Translation Methods of The Good Wife From Functional Equivalence Perspective
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作者 WANG Ya-kun BAO De-wang 《Journal of Literature and Art Studies》 2026年第1期26-30,共5页
The Good Wife is an American TV series that focuses on women’s independence,politics,and law.The drama has been remade in China,Japan,and South Korea.This research aims to use Nida’s Functional Equivalence Theory to... The Good Wife is an American TV series that focuses on women’s independence,politics,and law.The drama has been remade in China,Japan,and South Korea.This research aims to use Nida’s Functional Equivalence Theory to analyze the methods of its English-to-Chinese subtitle translation by considering social,cultural,and historic backgrounds between China and America.After data collection and case analysis,the study found that:(1)Five major translation methods are adopted in the subtitle translation of The Good Wife.They are free translation,variation,literal translation,addition,and omission.Among them,free translation is the most frequently used,while omission is used least.(2)The subtitle translation of films and TV series is limited by time and space restrictions,social-cultural differences,and other factors.When translating,translators should try to use humorous words,euphemism,intonation,and other ways,and combine different methods such as literal translation,free translation,variation,addition,omission,and other methods to seek equivalence both in the meaning and function of subtitles under the guidance of Functional Equivalence Theory. 展开更多
关键词 subtitle translation Functional Equivalence Theory The Good Wife translation methods
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Fourth Order Compact Finite Volume Methods for 1D Elliptic and Parabolic Equations on Non-uniform Meshes
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作者 ZHOU Lei WANG Feng WANG Tongke 《应用数学》 北大核心 2026年第2期342-359,共18页
This paper studies high order compact finite volume methods on non-uniform meshes for one-dimensional elliptic and parabolic differential equations with the Robin boundary conditions.An explicit scheme and an implicit... This paper studies high order compact finite volume methods on non-uniform meshes for one-dimensional elliptic and parabolic differential equations with the Robin boundary conditions.An explicit scheme and an implicit scheme are obtained by discretizing the equivalent integral form of the equation.For the explicit scheme with nodal values,the algebraic system can be solved by the Thomas method.For the implicit scheme with both nodal values and their derivatives,the system can be implemented by a prediction-correction procedure,where in the correction stage,an implicit formula for recovering the nodal derivatives is introduced.Taking two point boundary value problem as an example,we prove that both the explicit and implicit schemes are convergent with fourth order accuracy with respect to some standard discrete norms using the energy method.Two numerical examples demonstrate the correctness and effectiveness of the schemes,as well as the indispensability of using non-uniform meshes. 展开更多
关键词 Two point boundary value problem Parabolic equation Robin boundary condition Non-uniform mesh Fourth order compact finite volume scheme Predictioncorrection method Error estimate
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Analysis of the Effectiveness and Teaching Satisfaction of Diversified Teaching Methods in Clinical Instruction for Operating Room Nursing Interns
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作者 Jie Gao Yuanrong Luo 《Journal of Clinical and Nursing Research》 2026年第2期40-46,共7页
Objective: To analyze the advantages of diversified teaching methods in the clinical instruction of operating room nursing interns. Methods: Twenty-one nursing interns who underwent internships in the operating room f... Objective: To analyze the advantages of diversified teaching methods in the clinical instruction of operating room nursing interns. Methods: Twenty-one nursing interns who underwent internships in the operating room from March 2023 to March 2024 were selected as the control group and received conventional teaching methods. Another twenty-one nursing interns who underwent internships in the operating room from April 2024 to April 2025 were selected as the experimental group and received diversified teaching methods. The teaching effects of the two groups were compared. Results: The experimental group scored higher than the control group in assessments, teaching satisfaction, and teaching quality evaluations, as well as in post-instruction professional identity scores (p < 0.05). Conclusion: Diversified teaching methods can enhance the professional competence of operating room nursing interns, cultivate their professional identity, and yield high teaching satisfaction, thereby improving teaching quality. 展开更多
关键词 Diversified teaching methods Operating room nursing interns Clinical instruction Teaching satisfaction
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Four Major Diseases Affecting Pear Trees and Their Prevention and Control Methods
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作者 Longfei LI Jintao XU +5 位作者 Minghui JI Huan LIU Lijuan GAO Yue YAO Gang NIU Baofeng HAO 《Plant Diseases and Pests》 2026年第1期1-3,13,共4页
This paper presents an overview of the pathogens, symptoms of damage, patterns of occurrence, and chemical control methods associated with four major pear tree diseases: pear scab, pear ring rot, pear anthracnose, and... This paper presents an overview of the pathogens, symptoms of damage, patterns of occurrence, and chemical control methods associated with four major pear tree diseases: pear scab, pear ring rot, pear anthracnose, and pear speckle. The objective is to provide valuable references for the scientific and precise prevention and management of diseases in pear orchards, thereby contributing to the production of high-quality and high-yield pear fruits. 展开更多
关键词 PEAR Disease PATHOGEN Symptoms of damage Patterns of occurrence Prevention and control methods
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基于Bootstrap-DEA模型的陕西省三级综合医院技术效率实证研究
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作者 张洁铭 陈鹏岗 《中国卫生信息管理杂志》 2026年第1期168-176,共9页
目的在公立医院高质量发展的政策背景下,探究陕西省三级综合医院技术效率并分析其影响因素,为完善政策和保障医院高质量发展提供决策参考。方法选取陕西省48所综合三级医院作为研究对象,运用Max DEA软件中的Bootstrap模块测算纠偏前后... 目的在公立医院高质量发展的政策背景下,探究陕西省三级综合医院技术效率并分析其影响因素,为完善政策和保障医院高质量发展提供决策参考。方法选取陕西省48所综合三级医院作为研究对象,运用Max DEA软件中的Bootstrap模块测算纠偏前后医院的相对效率值,选取的投入指标包括职工总数和实际开放床位数,产出指标包括年诊疗人次数、年出院人次数和病床使用率。运用Tobit模型分析技术效率的影响因素,选取有关医院高质量发展的医院运行管理指标,包括医院类型、城市类型、资源配置、工作负荷和工作效率,对医院的技术效率影响因素进行回归分析。结果陕西省48所综合三级医院间职工数和床位数差异较大,采用Bootstrap纠偏后,所有三级医院的技术效率得分均降低,纠偏前得分(均值0.767)高于纠偏后得分(均值0.643)。公立医院的纠偏后技术效率得分(均值0.654)高于民营医院的得分(均值0.566),但差异无统计学意义(P=0.327);位于省会城市的医院纠偏后技术效率得分(均值0.615)低于非省会城市的得分(均值0.666),但差异无统计学意义(P=0.180)。Tobit模型分析显示,资源配置维度的在职职工数与医院技术效率得分呈负相关,工作负荷与工作效率维度的总诊疗人次数、病床使用率和医院技术效率得分呈正相关。结论陕西省综合三级医院运行效率尚未达到最优,建议三级医院加强精细化管理,着重提高三级公立医院的总诊疗人次、加强医院床位管理、培育优秀临床人才。 展开更多
关键词 bootstrap-DEA模型 技术效率 陕西省 TOBIT模型 医院管理 医院信息挖掘
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Tunnel ahead prospecting methods and intelligent interpretation of adverse geology:A review
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作者 Shucai Li Bin Liu +4 位作者 Lei Chen Huaifeng Sun Lichao Nie Zhengyu Liu Yuxiao Ren 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第1期1-19,共19页
Geological prospecting and the identification of adverse geological features are essential in tunnel construction,providing critical information to ensure safety and guide engineering decisions.As tunnel projects exte... Geological prospecting and the identification of adverse geological features are essential in tunnel construction,providing critical information to ensure safety and guide engineering decisions.As tunnel projects extend into deeper and more mountainous terrains,engineers face increasingly complex geological conditions,including high water pressure,intense geo-stress,elevated geothermal gradients,and active fault zones.These conditions pose substantial risks such as high-pressure water inrush,largescale collapses,and tunnel boring machine(TBM)blockages.Addressing these challenges requires advanced detection technologies capable of long-distance,high-precision,and intelligent assessments of adverse geology.This paper presents a comprehensive review of recent advancements in tunnel geological ahead prospecting methods.It summarizes the fundamental principles,technical maturity,key challenges,development trends,and real-world applications of various detection techniques.Airborne and semi-airborne geophysical methods enable large-scale reconnaissance for initial surveys in complex terrain.Tunnel-and borehole-based approaches offer high-resolution detection during excavation,including seismic ahead prospecting(SAP),TBM rock-breaking source seismic methods,fulltime-domain tunnel induced polarization(TIP),borehole electrical resistivity,and ground penetrating radar(GPR).To address scenarios involving multiple,coexisting adverse geologies,intelligent inversion and geological identification methods have been developed based on multi-source data fusion and artificial intelligence(AI)techniques.Overall,these advances significantly improve detection range,resolution,and geological characterization capabilities.The methods demonstrate strong adaptability to complex environments and provide reliable subsurface information,supporting safer and more efficient tunnel construction. 展开更多
关键词 Tunnel geological ahead prospecting Complex geological and environmental conditions Airborne geophysical methods Tunnel geophysical detection Borehole geophysical prospecting Intelligent geological interpretation
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Bootstrap抽样下基于贝叶斯估计的地震人员死亡评估研究
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作者 赵煜 魏毛毛 +2 位作者 孙艳萍 史一彤 陈文凯 《地震研究》 北大核心 2025年第1期132-140,共9页
选取1950-2022年中国内地地区历史震例数据信息,以极震区烈度、发震时间及人口密度为主要影响因素,建立三级场景,运用Bootstrap抽样方法对各场景下的历史震例进行扩充,进而采用贝叶斯估计给出不同场景下地震人员死亡变化分布函数,再根... 选取1950-2022年中国内地地区历史震例数据信息,以极震区烈度、发震时间及人口密度为主要影响因素,建立三级场景,运用Bootstrap抽样方法对各场景下的历史震例进行扩充,进而采用贝叶斯估计给出不同场景下地震人员死亡变化分布函数,再根据实际情况对此分布函数进行截断分析,以明确地震人员死亡的不确定性变化范围及死亡率区间概率值,最后随机选取历史地震灾害事件验证模型精度。结果表明:①各场景的死亡率均值及95%死亡率区间基本符合在极震区烈度相等并且人口密度条件下夜间死亡率大于白天死亡率的规律;②模型估计死亡人数区间能够较好覆盖实际上报的死亡人数。 展开更多
关键词 地震 人员死亡 bootstrap抽样 贝叶斯估计 死亡率
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基于加权bootstrap方法的交通流多变点实证分析
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作者 李扬 吴密霞 《数理统计与管理》 北大核心 2025年第3期427-435,共9页
本文研究了具有多个均值变点的噪声序列的变点估计及序列各点均值的置信区间问题。考虑到动态规划(Dynamic Programming,DP)算法可实现最优样本分割的优点,本文结合加权bootstrap和DP算法,提出了一种新的变点估计方法以及序列中各点均... 本文研究了具有多个均值变点的噪声序列的变点估计及序列各点均值的置信区间问题。考虑到动态规划(Dynamic Programming,DP)算法可实现最优样本分割的优点,本文结合加权bootstrap和DP算法,提出了一种新的变点估计方法以及序列中各点均值的置信区间方法。并将该方法应用于深圳的实际交通流数据,探索工作日和休息日南北不同方向交通流数据的特点。 展开更多
关键词 多均值变点 动态规划算法 bootstrap 置信区间 交通流变点
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基于Bootstrap改进的机床主轴可靠性建模
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作者 张孟 李传军 +3 位作者 苗百然 董颖怀 杨保鹏 李演刚 《计算机集成制造系统》 北大核心 2025年第9期3401-3410,共10页
随着数控机床主轴故障率的下降,针对正常工况的机床来说,想要获得大量的样本故障数据愈加困难,因此针对小样本数据的主轴平均故障间隔时间(MTBF)估计尤为关键。目前已有很多Bootstrap(自助法)的改进方法研究,但是多数抽样方式集中于数... 随着数控机床主轴故障率的下降,针对正常工况的机床来说,想要获得大量的样本故障数据愈加困难,因此针对小样本数据的主轴平均故障间隔时间(MTBF)估计尤为关键。目前已有很多Bootstrap(自助法)的改进方法研究,但是多数抽样方式集中于数据区间内,没有考虑向分组区间外扩充。文中采用改进Bootstrap法在三个方向上扩充原始样本,利用扩充后的样本来估计威布尔分布的尺度参数和形状参数,进而计算机床主轴的MTBF,将其值与改进前的自助法进行比较,改进后的方法既能提升数据扩容效率,又能提高MTBF估计精度,结合相关系数法不仅拓展了初值范围,而且简化了位移参数估计过程,因此建立三参数威布尔分布模型,得到更加精确的数控机床主轴可靠性参考指标,对工程实践有较高的参考价值。 展开更多
关键词 平均故障间隔时间 数控机床主轴 小样本 bootstrap 三参数威布尔
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带趋势项序列的持久性变点的Sieve Bootstrap检验
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作者 樊璐 赵文芝 王慧敏 《高师理科学刊》 2025年第3期18-23,共6页
用Sieve Bootstrap方法检验带趋势项序列的持久性变点从短记忆到长记忆的持久性变化.对序列进行去趋势变换,基于去趋势后的序列构造Ratio型检验统计量,通过重新采样残差构建SieveBootstrap统计量,证明Mallow测度下的一致性.通过模拟研... 用Sieve Bootstrap方法检验带趋势项序列的持久性变点从短记忆到长记忆的持久性变化.对序列进行去趋势变换,基于去趋势后的序列构造Ratio型检验统计量,通过重新采样残差构建SieveBootstrap统计量,证明Mallow测度下的一致性.通过模拟研究和实例分析验证了方法的有效性. 展开更多
关键词 序列 短记忆 长记忆 持久性变点 比率 Sieve bootstrap检验
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Performance investigation of LAMBDA and bootstrapping methods for PPP narrow-lane ambiguity resolution
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作者 Omer Faruk Atiz Sermet Ogutcu +2 位作者 Salih Alcay Pan Li Ilkay Bugdayci 《Geo-Spatial Information Science》 SCIE EI CSCD 2021年第4期604-614,共11页
Precise point positioning with ambiguity resolution(PPP-AR)is a powerful tool for geodetic and time-constrained applications that require high precision.The performance of PPP-AR highly depends on the reliability of t... Precise point positioning with ambiguity resolution(PPP-AR)is a powerful tool for geodetic and time-constrained applications that require high precision.The performance of PPP-AR highly depends on the reliability of the correct integer carrier-phase ambiguity estimation.In this study,the performance of narrow-lane ambiguity resolution of PPP using the Least-squares AMBiguity Decorrelation(LAMBDA)and bootstrapping methods is extensively investigated using real data from 55 IGS stations over one-month in 2020.Static PPP with 24-,12-,8-,4-,2-,1-and½-h sessions using two different cutoff angles(7°and 30°)was conducted with three PPP modes:i.e.ambiguity-float and two kinds of ambiguity-fixed PPP using the LAMBDA and bootstrapping methods for narrow-lane AR,respectively.The results show that the LAMBDA method can produce more reliable results for 2 hour and shorter observation sessions com-pared with the bootstrapping method using a 7°cutoff angle.For a 30°cutoff angle,the LAMBDA method outperforms the bootstrapping method for observation sessions of 4 h and less.For long observation times,the bootstrapping method produced much more accurate coordinates compared with the LAMBDA method without considering the wrong fixes cases.The results also show that occurrences of fixing the wrong integer ambiguities using the bootstrapping method are higher than that of the LAMBDA method. 展开更多
关键词 Ambiguity resolution narrow-lane Precise point positioning(PPP) LAMBDA bootstrapPING
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Structural Modal Parameter Recognition and Related Damage Identification Methods under Environmental Excitations:A Review 被引量:7
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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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基于Bootstrap方法对测风数据插补不确定性的分析研究 被引量:1
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作者 刘松 李伟岩 《太阳能》 2025年第7期62-70,共9页
为了准确评估风电场场区的风能资源,必须对测风塔的测风数据进行缺测与不合理数据的插补延长。测量-关联-预测(MCP)插补方法是利用测风塔短期测风数据和长期参证数据对测风塔缺测与不合理数据进行插补延长,但由此会产生数据处理不确定性... 为了准确评估风电场场区的风能资源,必须对测风塔的测风数据进行缺测与不合理数据的插补延长。测量-关联-预测(MCP)插补方法是利用测风塔短期测风数据和长期参证数据对测风塔缺测与不合理数据进行插补延长,但由此会产生数据处理不确定性,会对后续风电场发电量计算的准确性产生影响,因此需对插补不确定性进行分析。收集了位于中国不同地区、不同地形的2座测风塔的原始测风数据,采用MCP插补方法中常用的线性最小二乘(LLS)法对测风数据进行了插补,基于Bootstrap方法对LLS法带来的测风数据插补不确定性进行了定量分析,并对不同测风时长给测风数据插补不确定性带来的影响进行了分析。研究结果表明:1)残差自助法可以有效估计LLS法插补参数的不确定性,且插补参数的不确定性随着测风时长的增加而不断降低。2)LLS法插补结果受测风时长的影响较大。随着测风时长增加,LLS法带来的测风数据插补不确定性逐渐降低。测风塔测风数据与参考数据之间的相关系数越高,LLS法带来的测风数据插补不确定性越低。3)LLS法插补参数的不确定性对总预测不确定性的贡献较小,导致大量风速实测值基本落在95%置信区间之外。因此,后续需要进一步分析风速测量不确定性及不同MCP插补方法对测风数据插补不确定性的影响。 展开更多
关键词 测风数据 风电场 测量-关联-预测插补方法 bootstrap方法 线性最小二乘法 不确定性
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基于bootstrap方法的实验误差分析 被引量:2
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作者 张潮 张雁华 《质量与认证》 2025年第2期110-112,共3页
在实验测量中,通过统计学bootstrap方法对直接观察量样本重复抽样,可估计间接观察量分布并计算其误差。随着样本数量的增加,bootstrap方法和误差传递理论分析结果均会出现随机误差显著减小的特征,当样本数量固定时,改变bootstrap重复抽... 在实验测量中,通过统计学bootstrap方法对直接观察量样本重复抽样,可估计间接观察量分布并计算其误差。随着样本数量的增加,bootstrap方法和误差传递理论分析结果均会出现随机误差显著减小的特征,当样本数量固定时,改变bootstrap重复抽样次数,间接观察量误差变化并不明显,即抽样次数存在饱和值。因此,适当选取样本数量和重复抽样次数,通过bootstrap方法可有效减小实验测量次数,达到节省实验时间、空间以及计算资源等目的。 展开更多
关键词 bootstrap方法 误差传递公式 随机误差
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病例队列设计下可加可乘风险模型的Bootstrap估计
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作者 陈佳琪 《数理统计与管理》 北大核心 2025年第1期106-118,共13页
本文聚焦于病例队列设计的研究,旨在解决协变量测量成本高昂和疾病发病率较低等现实问题。该方法可以显著降低大规模预测性研究的成本。针对病例队列数据下的可加可乘风险模型,本文提出了三种估计方法,并采用了一种单阶段重抽样的非参数... 本文聚焦于病例队列设计的研究,旨在解决协变量测量成本高昂和疾病发病率较低等现实问题。该方法可以显著降低大规模预测性研究的成本。针对病例队列数据下的可加可乘风险模型,本文提出了三种估计方法,并采用了一种单阶段重抽样的非参数bootstrap方法进行协方差估计。通过数值模拟研究,我们将bootstrap方法获得的协方差估计与基于渐近理论的协方差估计进行了比较。结果显示,bootstrap方法表现出色。此外,我们将所提方法应用到一个实际案例中,取得了良好的分析效果。 展开更多
关键词 可加可乘风险模型 bootstrap方法 病例队列设计 简单随机抽样 单阶段重抽样 加权估计函数
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基于Bootstrap框架的高校图书馆座位预约网页设计
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作者 杨明 《信息记录材料》 2025年第6期95-97,共3页
高校图书馆座位资源紧张,传统选座方式效率低。本文设计了基于Bootstrap框架的高校图书馆座位预约网页,以解决传统选座方式效率低、资源分配不均的问题。本文采用Bootstrap框架构建前端界面,实现响应式导航栏、用户表单验证、座位状态... 高校图书馆座位资源紧张,传统选座方式效率低。本文设计了基于Bootstrap框架的高校图书馆座位预约网页,以解决传统选座方式效率低、资源分配不均的问题。本文采用Bootstrap框架构建前端界面,实现响应式导航栏、用户表单验证、座位状态可视化展示、预约操作即时反馈和提醒设置弹窗设计。后端采用Django框架,实现数据交互与业务逻辑处理,并采用MySQL数据库存储信息。实验结果表明:该系统能够有效提高座位预约的效率,优化资源分配,提升用户体验。基于Bootstrap框架的高校图书馆座位预约网页设计是可行的,具有良好的应用前景。 展开更多
关键词 高校图书馆 座位预约 bootstrap框架 技术实现 安全设计
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Data-Model Fusion Methods and Applications Toward Smart Manufacturing and Digital Engineering 被引量:1
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作者 Fei Tao Yilin Li +2 位作者 Yupeng Wei Chenyuan Zhang Ying Zuo 《Engineering》 2025年第12期36-50,共15页
As pivotal supporting technologies for smart manufacturing and digital engineering,model-based and data-driven methods have been widely applied in many industrial fields,such as product design,process monitoring,and s... As pivotal supporting technologies for smart manufacturing and digital engineering,model-based and data-driven methods have been widely applied in many industrial fields,such as product design,process monitoring,and smart maintenance.While promising,both methods have issues that need to be addressed.For example,model-based methods are limited by low computational accuracy and a high computational burden,and data-driven methods always suffer from poor interpretability and redundant features.To address these issues,the concept of data-model fusion(DMF)emerges as a promising solution.DMF involves integrating model-based methods with data-driven methods by incorporating big data into model-based methods or embedding relevant domain knowledge into data-driven methods.Despite growing efforts in the field of DMF,a unanimous definition of DMF remains elusive,and a general framework of DMF has been rarely discussed.This paper aims to address this gap by providing a thorough overview and categorization of both data-driven methods and model-based methods.Subsequently,this paper also presents the definition and categorization of DMF and discusses the general framework of DMF.Moreover,the primary seven applications of DMF are reviewed within the context of smart manufacturing and digital engineering.Finally,this paper directs the future directions of DMF. 展开更多
关键词 Data-model fusion Model-based methods Data-driven methods Smart manufacturing Digital engineering
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