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RF CMOS、BiCMOS的新进展(五)——移相器、RF开关、集成无源元件和相控阵(续)
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作者 李永 赵正平 《半导体技术》 北大核心 2026年第2期109-118,共10页
当今信息社会已进入通用人工智能时代,大数据呈指数规律增长,不但要求数据处理速度高速增长,同时也要求数据的传输带宽更宽,推动数据载波的频率向射频(RF)的高端发展。Si基RF CMOS和RF BiCMOS集成电路(IC)具有体积小、功耗低、易于集成... 当今信息社会已进入通用人工智能时代,大数据呈指数规律增长,不但要求数据处理速度高速增长,同时也要求数据的传输带宽更宽,推动数据载波的频率向射频(RF)的高端发展。Si基RF CMOS和RF BiCMOS集成电路(IC)具有体积小、功耗低、易于集成等优点,相应呈现高速发展的态势。综述了Si基RF CMOS和RF BiCMOS的最新进展和发展态势,主要包括低噪声放大器与接收前端,射频-直流整流器与射频能量收集器,功率放大器、RF信号放大器与发射机,振荡器、混频器与频率综合器,移相器、开关、集成无源元件和相控阵,RF专用集成电路(ASIC)和微系统集成等七个RF IC发展的主要方面,凝练了各类RF IC的发展趋势和关键技术创新点。 展开更多
关键词 射频(rf)CMOS rf BiCMOS 放大器 收/发机 rf能量收集器 压控振荡器 频率综合器 移相器 相控阵 微系统集成
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RF CMOS、BiCMOS的新进展(六)——RF ASIC和微系统集成
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作者 李永 赵正平 《半导体技术》 北大核心 2026年第3期205-214,共10页
当今信息社会已进入通用人工智能时代,大数据呈指数规律增长,不但要求数据处理速度高速增长,同时也要求数据的传输带宽更宽,推动数据载波的频率向射频(RF)的高端发展。Si基RF CMOS和RF BiCMOS集成电路(IC)具有体积小、功耗低、易于集成... 当今信息社会已进入通用人工智能时代,大数据呈指数规律增长,不但要求数据处理速度高速增长,同时也要求数据的传输带宽更宽,推动数据载波的频率向射频(RF)的高端发展。Si基RF CMOS和RF BiCMOS集成电路(IC)具有体积小、功耗低、易于集成等优点,相应呈现高速发展的态势。综述了Si基RF CMOS和RF BiCMOS的最新进展和发展态势,主要包括低噪声放大器与接收前端,射频-直流整流器与射频能量收集器,功率放大器、RF信号放大器与发射机,振荡器、混频器与频率综合器,移相器、开关、集成无源元件和相控阵,RF专用集成电路(ASIC)和微系统集成等七个RF IC发展的主要方面,凝练了各类RF IC的发展趋势和关键技术创新点。 展开更多
关键词 射频(rf)CMOS rf BiCMOS 放大器 收/发机 rf能量收集器 压控振荡器 频率综合器 移相器 相控阵 微系统集成
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RF CMOS、BiCMOS的新进展(五)——移相器、RF开关、集成无源元件和相控阵
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作者 李永 赵正平 《半导体技术》 北大核心 2026年第1期1-12,共12页
当今信息社会已进入通用人工智能时代,大数据呈指数规律增长,不但要求数据处理速度高速增长,同时也要求数据的传输带宽更宽,推动数据载波的频率向射频(RF)的高端发展。Si基RF CMOS和RF BiCMOS集成电路(IC)具有体积小、功耗低、易于集成... 当今信息社会已进入通用人工智能时代,大数据呈指数规律增长,不但要求数据处理速度高速增长,同时也要求数据的传输带宽更宽,推动数据载波的频率向射频(RF)的高端发展。Si基RF CMOS和RF BiCMOS集成电路(IC)具有体积小、功耗低、易于集成等优点,相应呈现高速发展的态势。综述了Si基RF CMOS和RF BiCMOS的最新进展和发展态势,主要包括低噪声放大器与接收前端,射频-直流整流器与射频能量收集器,功率放大器、RF信号放大器与发射机,振荡器、混频器与频率综合器,移相器、开关、集成无源元件和相控阵,RF专用集成电路(ASIC)和微系统集成等七个RF IC发展的主要方面,凝练了各类RF IC的发展趋势和关键技术创新点。 展开更多
关键词 射频(rf)CMOS rf BiCMOS 放大器 收/发机 rf能量收集器 压控振荡器 频率综合器 移相器 相控阵 微系统集成`
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基于AHC-PSO-RF代理模型的大型集装箱船参数横摇运动快速预报
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作者 孙强 谭杰 周耀华 《中国舰船研究》 北大核心 2026年第1期104-113,共10页
[目的]针对传统基于水动力学的数值模拟方法计算船舶参数横摇存在计算成本高、操作要求高且无法覆盖所有装载工况等问题,提出一种融合特征物理化重构、凝聚层次聚类(AHC)与改进随机森林(RF)的集成机器学习替代模型,用于高效预测船舶参... [目的]针对传统基于水动力学的数值模拟方法计算船舶参数横摇存在计算成本高、操作要求高且无法覆盖所有装载工况等问题,提出一种融合特征物理化重构、凝聚层次聚类(AHC)与改进随机森林(RF)的集成机器学习替代模型,用于高效预测船舶参数横摇幅值。[方法]利用AHC压缩特征维度,降低模型复杂度和计算开销;采用粒子群算法(PSO)对RF超参数进行全局寻优。[结果]基于某大型集装箱船多工况水动力数值模拟结果数据的验证结果表明:与广义回归神经网络(GRNN)及未优化RF模型相比,在迎浪和艉随浪工况下,该模型(AHC–PSO–RF)在横摇有义值预测中的决定系数(R2)平均提升5.84%与0.27%,均方根误差(RMSE)平均降低59.28%与10.69%,预测精度较高。此外,模型在单个装载工况的平均计算耗时相比于水动力数值模拟方法减少84.5%。[结论]该模型在批量预测任务中具备显著效率优势,证明了其作为高效替代方案的工程实用价值。 展开更多
关键词 船舶稳性 参数横摇 代理模型 凝聚层次聚类−粒子群优化−随机森林模型 集装箱船 动稳性预报
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基于随机森林算法(RF)的深层煤岩气CO_(2)与N_(2)伴注压裂协同增效机制
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作者 方燕俊 罗懿 王帆 《非常规油气》 2026年第1期63-72,共10页
针对深层煤岩气藏吸附气解吸困难、压后产能低和递减快等问题,在CO_(2)与N_(2)对煤层作用机制的基础上,以鄂尔多斯盆地大牛地深层煤岩气为研究对象,通过开展甲烷解吸性能测试、岩心伤害测试以及返排液滞留测试等室内实验,进行地层条件... 针对深层煤岩气藏吸附气解吸困难、压后产能低和递减快等问题,在CO_(2)与N_(2)对煤层作用机制的基础上,以鄂尔多斯盆地大牛地深层煤岩气为研究对象,通过开展甲烷解吸性能测试、岩心伤害测试以及返排液滞留测试等室内实验,进行地层条件下不同注气压力、气液体积比和气体配比等伴注参数混合气伴注对煤岩润湿性能、微观结构、表面电荷性质以及对甲烷解吸性能的影响因素分析,同时结合随机森林算法(RF),明确了滑溜水压裂液对深层煤岩气解吸性能影响的主控因素和预测主控因素边界条件。研究表明,气体与液体共存条件下,压裂液对煤岩的伤害占主导地位,注气可以减缓压裂液对煤岩的伤害;Zeta电位、质量差、接触角和注气压力是煤岩气解吸影响的主控因素,当气液配比为1∶4、V(N_(2))∶V(CO_(2))=1∶3~1∶4(温度80℃,压力5 MPa),浸泡后煤样与水的接触角控制在30°~40°、Zeta电位控制在-60~-70mV,最有利于提高甲烷的解吸量,同时考虑CO_(2)成本高于N_(2),V(N_(2))∶V(CO_(2))=1∶3效益最佳。 展开更多
关键词 深层煤岩气 混合气伴注 解吸 CO_(2) N_(2) 随机森林算法(rf)
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基于RBFNN-RF的南水北调中线总干渠冰情预测模型
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作者 陈晓楠 刘爽 +3 位作者 陈宁 李晓倩 穆祥鹏 段春青 《水利水电快报》 2026年第1期1-7,共7页
为提升南水北调中线总干渠冰期输水能力,实现在保障冰期安全运行前提下尽可能多供水的目标,精准预测总干渠冰情有重要意义。利用南水北调中线工程通水以来的冰情原型观测数据,应用径向基神经网络(RBFNN)建立了当日平均水温、次日最高和... 为提升南水北调中线总干渠冰期输水能力,实现在保障冰期安全运行前提下尽可能多供水的目标,精准预测总干渠冰情有重要意义。利用南水北调中线工程通水以来的冰情原型观测数据,应用径向基神经网络(RBFNN)建立了当日平均水温、次日最高和最低气温、次日天气状况、次日水流流速与次日平均水温的非线性回归模型,利用随机森林(RF)模型建立了基于水温、气温、流速因子研判冰情状态的二分类模型,并结合两者形成了基于径向基神经网络和随机森林(RBFNN-RF)的冰情逐日预测模型。以南水北调中线总干渠北拒马河断面为典型代表,应用该模型分别针对1,3,5,7 d预见期的冰情进行测试。结果表明:1,3,5,7 d预测水温的均方根误差分别为0.17,0.36,0.52,0.64℃,而相应预见期下的冰情状态预测准确率分别为95.28%,92.68%,89.08%和85.22%,建立的冰情预测模型具有较高的精度。该冰情预测模型可为南水北调中线工程实施精准动态调度,充分发挥工程效益提供技术支撑,并为类似明渠长距离调水工程的冰期调度提供参考。 展开更多
关键词 冰情预测 RBFNN rf 南水北调中线总干渠
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基于RF-Transformer的测井曲线页岩岩相识别方法
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作者 苏俊磊 董旭 +4 位作者 唐嘉伟 曾渝 石雪莹 李佩璇 杨仁杰 《测井技术》 2026年第1期153-162,共10页
岩相识别是油气储层精细刻画的关键环节,其准确性直接影响储层评价结果的可靠性。现有识别方法在测井数据高频噪声抑制方面存在不足,且难以准确捕捉地层纵向长程依赖关系。因此,本文提出了一种融合随机森林(Random Forest,RF)与Transfor... 岩相识别是油气储层精细刻画的关键环节,其准确性直接影响储层评价结果的可靠性。现有识别方法在测井数据高频噪声抑制方面存在不足,且难以准确捕捉地层纵向长程依赖关系。因此,本文提出了一种融合随机森林(Random Forest,RF)与Transformer的深度学习模型(RF-Transformer),以提高非均质储层页岩岩相识别的准确性与效率,为储层精细刻画提供技术支撑。该模型首先利用随机森林模型评估测井曲线(如自然伽马、声波时差、电阻率等)特征权重,用以筛选关键参数进而压制高频噪声,构建高质量特征输入向量。随后用Transformer模块,借助其自注意力机制的全局上下文感知能力,并行计算测井曲线的关联权重,从而深度挖掘并重构地层纵向长程依赖关系。以川南页岩气田3800个实测样本(含6类典型岩相、8条常规测井曲线)为数据集,开展模型性能对比与实例应用分析。结果表明:①RF-Transformer模型准确率达91.51%,较Transformer、长短期记忆网络(Long Short-Term Memory,LSTM)和卷积神经网络(Convolutional Neural Network,CNN)模型分别提升了12.90%、23.60%和47.54%,优于K近邻(81.09%)、决策树(77.28%)等传统机器学习模型;②该模型仅需约25次迭代即可进入收敛态,收敛速度较现有模型提升8~10倍;③成功筛选出自然伽马、声波时差、浅侧向电阻率等6条关键测井曲线,有效剔除深侧向电阻率等冗余特征与非地质噪声;④实例应用中,预测页岩岩相剖面纵向连续性与平滑度高,与真实地质分层特征高度吻合,精准刻画页岩岩相过渡带边界。结论认为,该模型在兼顾高抗噪性与强时序捕捉能力的同时,实现页岩岩相的高效精准识别,为非均质储层精细描述提供了可靠技术支撑,后续需围绕测井解释软件适配性展开优化。 展开更多
关键词 测井曲线 岩相识别 随机森林(Random Forest rf) 深度学习 TRANSFORMER 页岩储层 长程依赖 噪声抑制
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Local Electric Fields Coupled with Cl^(−)Fixation Strategy for Improving Seawater Oxygen Reduction Reaction Performance
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作者 Yu-Rong Liu Miao Zhang +8 位作者 Yan-Hui Yu Ya-Lin Liu Jing Li Xiao-Dong Shi Zhen-Ye Kang Dao-Xiong Wu Peng Rao Ying Liang Xin-Long Tian 《电化学(中英文)》 北大核心 2025年第9期46-55,共10页
Development of robust electrocatalyst for oxygen reduction reaction(ORR)in a seawater electrolyte is the key to realize seawater electrolyte-based zinc-air batteries(SZABs).Herein,constructing a local electric field c... Development of robust electrocatalyst for oxygen reduction reaction(ORR)in a seawater electrolyte is the key to realize seawater electrolyte-based zinc-air batteries(SZABs).Herein,constructing a local electric field coupled with chloride ions(Cl-)fixation strategy in dual single-atom catalysts(DSACs)was proposed,and the resultant catalyst delivered considerable ORR performance in a seawater electrolyte,with a high half-wave potential(E_(1/2))of 0.868 V and a good maximum power density(Pmax)of 182 mW·cm^(−2)in the assembled SZABs,much higher than those of the Pt/C catalyst(E_(1/2):0.846 V;Pmax:150 mW·cm^(−2)).The in-situ characterization and theoretical calculations revealed that the Fe sites have a higher Cl^(−)adsorption affinity than the Co sites,and preferentially adsorbs Cl^(−)in a seawater electrolyte during the ORR process,and thus constructs a low-concentration Cl^(−)local microenvironment through the common-ion exclusion effect,which prevents Cl^(−)adsorption and corrosion in the Co active centers,achieving impressive catalytic stability.In addition,the directional charge movement between Fe and Co atomic pairs establishes a local electric field,optimizing the adsorption energy of Co sites for oxygen-containing intermediates,and further improving the ORR activity. 展开更多
关键词 Seawater zinc-air battery Oxygen reduction reaction Local electric field Chloride ion fixation strategy Sin-gle-atom catalyst
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融合TAM-LSTNet-CEEMDAN-RF误差修正模型的工艺质量预测算法
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作者 侯步超 阴艳超 +3 位作者 张曦 汪霖宇 陈忠 洪志敏 《机械科学与技术》 北大核心 2026年第1期94-103,共10页
针对传统流程生产工艺质量预测模型训练过程中存在误差积累的问题,提出一种融合注意力机制-长短时间序列网络-自适应噪声集成经验模态分解-随机森林(TAM-LSTNet-CEEMDAN-RF)误差修正的组合预测模型。首先通过引入互信息和堆叠稀疏自编码... 针对传统流程生产工艺质量预测模型训练过程中存在误差积累的问题,提出一种融合注意力机制-长短时间序列网络-自适应噪声集成经验模态分解-随机森林(TAM-LSTNet-CEEMDAN-RF)误差修正的组合预测模型。首先通过引入互信息和堆叠稀疏自编码器,从工艺数据中筛选出有效的特征,构建有效维度;然后利用TAM-LSTNet模型挖掘有效维度与工艺时间序列数据之间的复杂关联关系,得出第一值并与测试值相减,计算出误差序列,通过CEEMDAN-RF模型对误差序列进行校正,得出第二值;最后将两值相加处理,得到质量指标预测值。结合某流程生产线的数据进行分析验证,结果表明:组合模型的拟合度较TAM-LSTM模型和TAM-LSTNet-RF模型分别提高了0.036、0.029,验证了所提方法的有效性和适用性;所提误差修正模型可实现流程生产质量的准确预测。 展开更多
关键词 TAM-LSTNet-CEEMDAN-rf 误差修正模型 工艺质量预测
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Atomistic simulation of batteries via machine learning force fields:From bulk to interface
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作者 Jinkai Zhang Yaopeng Li +5 位作者 Ming Chen Jiaping Fu Liang Zeng Xi Tan Tian Sun Guang Feng 《Journal of Energy Chemistry》 2025年第7期911-929,共19页
Batteries play a critical role in electric vehicles and distributed energy generation.With the growing demand for energy storage solutions,new battery materials and systems are continually being developed.In this proc... Batteries play a critical role in electric vehicles and distributed energy generation.With the growing demand for energy storage solutions,new battery materials and systems are continually being developed.In this process,molecular dynamics(MD)simulations can reveal the microscopic mechanisms of battery processes,thereby boosting the design of batteries.Compared to other MD simulation techniques,the machine learning force field(MLFF)holds the advantages of first-principles accuracy along with large spatial and temporal scale,offering opportunities to uncover new mechanisms in battery systems.This review presents a detailed overview of the fundamental principles and model types of MLFFs,as well as their applications in simulating the structure,transport properties,and chemical reaction properties of bulk battery materials and interfaces.Notably,we emphasize the long-range interaction corrections and constant-potential methods in the model design of MLFFs.Finally,we discuss the challenges and prospects of applying MLFF models in the research of batteries. 展开更多
关键词 BATTERY Machine learning force field Molecular dynamics INTErfACES
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基于FHSPSO-RF的交通事故严重程度预测
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作者 王淑椒 胡学龙 唐磊 《山东交通学院学报》 2026年第1期25-33,共9页
为提高交通事故严重程度的预测准确性,构建一种基于觅食生境选择粒子群优化(foraging habitat selection particle swarm optimization,FHSPSO)算法优化随机森林(random forest,RF)算法关键超参数的FHSPSO-RF模型,以美国华盛顿州西雅图... 为提高交通事故严重程度的预测准确性,构建一种基于觅食生境选择粒子群优化(foraging habitat selection particle swarm optimization,FHSPSO)算法优化随机森林(random forest,RF)算法关键超参数的FHSPSO-RF模型,以美国华盛顿州西雅图市2022年1月至2023年2月的交通事故数据为基础,选取12项特征指标,采用合成少数类过采样技术,增加重伤和死亡事故的样本数,改善事故类别分布均衡性;将FHSPSO-RF模型与支持向量机(support vector machine,SVM)、K近邻(K-nearest neighbors,KNN)和逻辑回归(logistic regression,LR)等模型进行性能对比,并通过SHAP(Shapley additive explanations)分析法,解析各特征对交通事故严重程度的影响机制。结果表明:过采样后重伤、死亡事故的召回率显著增大,FHSPSO-RF模型的整体性能更均衡;FHSPSO-RF模型的准确率、精确率、召回率、F1分数均高于其他3个模型,对交通事故严重程度的预测效果最好;在所有交通事故类型中,受伤人数和车辆数量均为最关键的驱动因素,对交通事故严重程度具有显著正向影响,行人数量、高冲击碰撞类型(如正面撞击)与复杂道路环境(如交叉口、匝道)是重伤及死亡事故的关键风险组合;财产损失事故与是否碰撞路边停放车辆密切相关。FHSPSORF模型在交通事故严重程度预测中表现出良好的性能与可解释性,可为交通事故风险预测与防控决策提供依据。 展开更多
关键词 交通事故 严重程度预测 FHSPSO rf
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Interface-engineered 3D ZnTe/MXene heterostructures with built-in electric fields for fast and durable potassium storage
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作者 Hong Geun Oh Seohyeon Jang +6 位作者 Ho Rim Kim Daiha Shin Jiung Cho Haeseong Jang Jin Koo Kim Inho Nam Seung-Keun Park 《Journal of Energy Chemistry》 2025年第12期462-473,I0013,共13页
Understanding dynamic storage mechanisms and tuning electrode interfaces is vital for designing highperformance potassium-ion battery(KIB)anodes.Despite their high capacities,transition metal telluride(TMTe)anodes oft... Understanding dynamic storage mechanisms and tuning electrode interfaces is vital for designing highperformance potassium-ion battery(KIB)anodes.Despite their high capacities,transition metal telluride(TMTe)anodes often suffer from sluggish K+diffusion and severe volume expansion during cycling,highlighting the need for structurally optimized and interface-engineered architectures.While such strategies have been proven to be effective in lithium-and sodium-ion batteries,their use in TMTe-based KIB anodes remains largely unexplored.In this study,we firstly introduce a heterointerface-engineered three-dimensional microsphere composed of ZnTe nanoparticles and uniformly encapsulated by MXene(denoted MX/ZnTe@NC).Importantly,a built-in electric field(BIEF)is induced at the MXeneZnTe interface due to their work function.This interfacial field modulates the local electronic structure and significantly accelerates K^(+)adsorption and diffusion kinetics,especially under high current densities.First-principles simulations and spectroscopic analyses confirm that the BIEF significantly increases the K~+adsorption strength and lowers the energy barriers for ion transport.Electrochemical analyses reveal that the MX/ZnTe@NC anode delivers a high reversible capacity of 283 mAh g^(-1)after 1000 cycles at 0.5 A g^(-1),with nearly 100%Coulombic efficiency.Even at 10 A g^(-1),the anode retains a capacity of 83 mAh g^(-1),indicating excellent rate performance.Additionally,in-situ and ex-situ characterizations reveal a highly reversible ZnTe conversion mechanism involving dynamic intermediate phases.This study provides mechanistic insight into the structural and chemical evolution during cycling and highlights the synergistic role of interfacial field engineering and three-dimensional heterostructure design in advancing MXene-based KIB anodes. 展开更多
关键词 Built-in electric field Heterostructure engineering Transition metal telluride MXene Potassium-ion batteries
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特征RF识别下空调集群直接负荷双层优化控制
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作者 郑元杰 丁毛毛 +1 位作者 付珺 严佳梅 《电子设计工程》 2026年第4期164-167,172,共5页
为更有效地管理电力系统中空调集群的电力需求,减少电压波动和负荷峰谷差,提高电网的稳定性和经济性,设计特征随机森林(Random Forest,RF)识别下的空调集群直接负荷双层优化控制方法。基于特征RF识别方法辨识空调用户群体,构建上层与下... 为更有效地管理电力系统中空调集群的电力需求,减少电压波动和负荷峰谷差,提高电网的稳定性和经济性,设计特征随机森林(Random Forest,RF)识别下的空调集群直接负荷双层优化控制方法。基于特征RF识别方法辨识空调用户群体,构建上层与下层的双层优化控制目标函数,采用遗传算法求解双层优化控制目标函数,实现直接负荷双层优化控制。测试结果表明,设计方法控制后系统的削峰成本降低至3元/(kW·h)以下,电压水平比较稳定。 展开更多
关键词 特征rf识别 空调集群 直接负荷控制 双层优化控制 目标函数
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Comparison of strain and temperature fields between Micro-NPR and PR anchor rods under uniaxial tension
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作者 ZHANG Weilong YANG Dong +2 位作者 TAO Zhigang GUO Yuhan ZHENG Hu 《Journal of Mountain Science》 2026年第1期370-379,共10页
The deformation characteristics and thermal response of anchor rods are crucial for ensuring the stability and safety of surrounding rock support structures.However,existing research has predominantly concentrated on ... The deformation characteristics and thermal response of anchor rods are crucial for ensuring the stability and safety of surrounding rock support structures.However,existing research has predominantly concentrated on the mechanical performance of anchor rods,with limited attention to the coupled evolution of strain and temperature fields during tensile deformation.This knowledge gap hinders a comprehensive understanding of the synergistic mechanical-thermal response mechanisms in anchor rods under loading conditions.To address this limitation,the present study systematically investigated the evolution of strain and temperature fields,along with their correlation,during the test of micro-negative Poisson's ratio(NPR)and ordinary Poisson's ratio(PR)anchor rods.Digital image correlation(DIC)and infrared thermography(IRT)techniques were employed for this exploration.The uniaxial tensile tests were conducted at two different rates,and the ordinary PR anchor rod(Q235 anchor rod)was established as a control group for comparative analysis.The findings reveal that the micro-NPR anchor rod exhibit strain localization at multiple locations during the tensile process,whereas Q235 anchors show local strain concentration in only one region.The standard deviation evolution curves for both the strain and temperature field exhibit two distinct phases in the two anchor rods.The evolution patterns between these two types of curves are basically consistent.The two standard deviation curves for the micro-NPR anchor rod display a wavy increase in the second phase,while for the Q235 anchor rod,they increase steadily until the specimen is damaged.The correlation analysis reveals that the standard deviations of strain and temperature differences for both types of anchor rods are significantly correlated.These findings demonstrate the synergistic evolution mechanism of deformation and thermal response,providing a potential foundation for utilizing thermal monitoring to assess the stability of rock support structures. 展开更多
关键词 Micro-NPR anchor rod Q235 anchor rod Strain field Temperature field Standard deviation Uniaxial tensile
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基于Optuna超参数优化的混凝土抗压强度预测RF机器学习模型优化研究
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作者 张凯敏 《新材料·新装饰》 2026年第5期26-29,共4页
抗压强度作为混凝土核心性能指标,直接影响混凝土结构安全与耐久性。传统抗压强度预测方法耗时且易受环境干扰,为准确预测混凝土的抗压强度,文章基于Optuna超参数优化的随机森林(RF)算法,从文献中筛选1030组混凝土试验数据,以此为基础... 抗压强度作为混凝土核心性能指标,直接影响混凝土结构安全与耐久性。传统抗压强度预测方法耗时且易受环境干扰,为准确预测混凝土的抗压强度,文章基于Optuna超参数优化的随机森林(RF)算法,从文献中筛选1030组混凝土试验数据,以此为基础对比了RF算法与XGBOost、KNN和SVM算法的混凝土抗压强度预测精度。在确定RF算法表现最优后,采用Optuna算法对其进行超参数优化。结果显示,无论是在训练集还是测试集中,RF算法的预测精度均领先于其他三种算法,而经Optuna超参数优化后,RF机器学习模型的预测精度得到进一步提升。本研究为混凝土抗压强度预测提供了高效精准的新方法,有助于提升工程设计科学性,推动相关工程领域技术进步。 展开更多
关键词 混凝土 抗压强度预测 Optuna rf机器学习模型
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Impedance of RF shield on ceramic chamber in the rapid cycling synchrotron of China Spallation Neutron Source
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作者 Liang‑Sheng Huang Bin Wu +6 位作者 Ming‑Yang Huang Ren‑Hong Liu Biao Tan Peng‑Cheng Wang Yong‑Chuan Xiao Li‑Rui Zeng Xiao Li 《Nuclear Science and Techniques》 2026年第1期130-140,共11页
In a rapid cycling synchrotron(RCS),the magnetic field is synchronized with the beam energy,creating a highly dynamic magnetic environment.A ceramic chamber with a shielding layer(RF shield),composed of a series of co... In a rapid cycling synchrotron(RCS),the magnetic field is synchronized with the beam energy,creating a highly dynamic magnetic environment.A ceramic chamber with a shielding layer(RF shield),composed of a series of copper strips connected to a capacitor at either end,is typically employed as a vacuum chamber to mitigate eddy current effects and beam coupling impedance.Consequently,the ceramic chamber exhibits a thin-walled multilayered complex structure.Previous theoretical studies have suggested that the impedance of such a structure has a negligible impact on the beam.However,recent impedance measurements of the ceramic chamber in the China Spallation Neutron Source(CSNS)RCS revealed a resonance in the low-frequency range,which was confirmed by further theoretical analysis as a source of beam instability in the RCS.Currently,the magnitude of this impedance cannot be accurately assessed using theoretical calculations.In this study,we used the CST Microwave Studio to confirm the impedance of the ceramic chamber.Further simulations covering six different types of ceramic chambers were conducted to develop an impedance model in the RCS.Additionally,this study investigates the resonant characteristics of the ceramic chamber impedance,finding that the resonant frequency is closely related to the capacitance of the capacitors.This finding provides clear directions for further impedance optimization and is crucial for achieving a beam power of 500 kW for the CSNS Phase-Ⅱ project(CSNS-Ⅱ).However,careful attention must be paid to the voltage across the capacitors. 展开更多
关键词 Beam coupling impedance Ceramic chamber rf shield RESONANCE High dynamic magnetic environment
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Boosting peroxymonosulfate activated for emerging contaminant removal:The synergy of boron doping in regulating the interfacial electric field of FeNC
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作者 Shiyu Zuo Yan Wang +2 位作者 Jinquan Wan Jianxin Yi JoséAlemáne 《Journal of Environmental Sciences》 2026年第1期97-107,共11页
Peroxymonosulfate(PMS)-based advanced oxidation processes(AOPs)are an effective way to remove emerging contaminants(ECs)from water.The catalytic process involving PMS is hindered by the suboptimal electron trans-fer e... Peroxymonosulfate(PMS)-based advanced oxidation processes(AOPs)are an effective way to remove emerging contaminants(ECs)from water.The catalytic process involving PMS is hindered by the suboptimal electron trans-fer efficiency of current catalysts,the further application of AOPs technology is limited.Here,it is proposed that the interfacial electric field can be controlled by bor(B)-doped FeNC catalysts,which shows significant advantages in the efficient generation,release and participation of reactive oxygen species(ROS)in the reaction.The super exchange interaction between Fe sites and N and B sites is realized through the directional transfer of electrons in the interfacial electric field,which ensures the high efficiency and stability of the PMS catalytic process.B doping increases the d orbitals distribution at Fermi level,which facilitates enhanced electron transition activity,thereby promoting the effective generation of (1)^O_(2).At the same time,orbital hybridization causes the center of the d band to move to a lower energy level,which not only contributes to the desorption process of (1)^O_(2),but also accelerates its release.In addition,B-doping also improved the adsorption capacity of organic pollutants and shortened the migration distance of ROS,thereby significantly improving the degradation efficiency of ECs.The B-doping strategy outlined offers a novel approach to the development of FeNC catalysts,it lays a theoretical foundation and offers technical insights for the integration of PMS/AOPs technology in the ECs management. 展开更多
关键词 Interfacial electric field Boron doping Electronic transfer PEROXYMONOSULFATE Emerging contaminants
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2021款江淮RF8混合动力车多个故障灯异常点亮
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作者 姜国 《汽车维护与修理》 2026年第3期57-57,共1页
故障现象一辆2021款江淮RF8混合动力车,搭载BHE15-BFZ发动机,累计行驶里程约为3.9万km,因仪表盘上的多个故障灯异常点亮而进店检修。故障诊断接车后试车,将车辆电源模式置于ON模式,发现仪表盘上的安全气囊故障灯、陡坡缓降指示灯、AUTOH... 故障现象一辆2021款江淮RF8混合动力车,搭载BHE15-BFZ发动机,累计行驶里程约为3.9万km,因仪表盘上的多个故障灯异常点亮而进店检修。故障诊断接车后试车,将车辆电源模式置于ON模式,发现仪表盘上的安全气囊故障灯、陡坡缓降指示灯、AUTOHOLD指示灯、制动系统故障报警灯、电子稳定系统指示灯、EPB故障报警灯等异常点亮(图1)。 展开更多
关键词 故障灯 AUTOHOLD指示灯 陡坡缓降指示灯 江淮rf8
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Violet Arsenic Phosphorus:Switching p-Type into High Performance n-Type Semiconductor by Arsenic Substitution
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作者 Rui Zhai Zhuorui Wen +7 位作者 Xuewen Zhao Junyi She Mengyue Gu Fanqi Bu Chang Huang Guodong Meng Yonghong Cheng Jinying Zhang 《Nano-Micro Letters》 2026年第5期93-106,共14页
Violet phosphorus,a recently explored layered elemental semiconductor,has attracted much attention due to its unique photoelectric,mechanical properties,and high hole mobility.Herein,violet arsenic phosphorus has for ... Violet phosphorus,a recently explored layered elemental semiconductor,has attracted much attention due to its unique photoelectric,mechanical properties,and high hole mobility.Herein,violet arsenic phosphorus has for the first time been synthesized by a molten lead method.The crystal structure of violet arsenic phosphorus(P^(83.4)As_(0.6),CSD-2408761)was determined by single crystal X-ray diffraction to have similar structure as that of violet phosphorus,where P12 is occupied by arsenic/phosphorus(As/P)atoms as mixed occupancy sites As1/P12.The arsenic substitution has been demonstrated to tune the band structure of violet phosphorus,switching p-type of violet phosphorus to high-performance n-type violet arsenic phosphorus.The effective electron mass along the<010>direction is significantly reduced from 1.792 to 0.515 m_(0)by arsenic substitution,resulting in an extremely high electron mobility of 2622.503 cm^(2)V^(-1)s^(-1).The field effect transistor built with P_(83.4)As_(0.6)nanosheets was measured to have a high electron mobility(137.06 cm^(2)V^(-1)s^(-1),61.2 nm),even under ambient conditions for 5 h,much higher than the hole mobility of violet phosphorene nanosheets(4.07 cm^(2)V^(-1)s^(-1),73.3 nm).This work provides a new idea for designing phosphorus-based materials for field effect transistors,giving significant potential in complementary metal-oxide-semiconductor applications. 展开更多
关键词 Violet phosphorus Arsenic substitution n-type semiconductor High mobility Field effect transistor
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Electric-Field-Driven Generative Nanoimprinting for Tilted Metasurface Nanostructures
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作者 Yu Fan Chunhui Wang +6 位作者 Hongmiao Tian Xiaoming Chen Ben QLi Zhaomin Wang Xiangming Li Xiaoliang Chen Jinyou Shao 《Nano-Micro Letters》 2026年第1期290-305,共16页
Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is p... Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is proposed.The electric field applied between the template and the substrate drives the contact,tilting,filling,and holding processes.By accurately controlling the introduced included angle between the flexible template and the substrate,tilted nanostructures with a controllable angle are imprinted onto the substrate,although they are vertical on the template.By flexibly adjusting the electric field intensity and the included angle,large-area uniform-tilted,gradient-tilted,and high-angle-tilted nanostructures are fabricated.In contrast to traditional replication,the morphology of the nanoimprinting structure is extended to customized control.This work provides a cost-effective,efficient,and versatile technology for the fabrication of various large-area tilted metasurface structures.As an illustration,a tilted nanograting with a high coupling efficiency is fabricated and integrated into augmented reality displays,demonstrating superior imaging quality. 展开更多
关键词 Generative nanoimprinting Electric field assistance Tilted metasurface structures Large-area fabrication
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