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The_(0)S_(0)fundamental mode excited by Sumatra-Andaman earthquake:Parameters assessment using the maximum likelihood method
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作者 Mikhail Vinogradov Vadim Milyukov 《Geodesy and Geodynamics》 2026年第2期259-266,共8页
This paper presents new estimations for all parameters(amplitude,frequency,quality factor,and initial phase)of the_(0)S_(0)Earth fundamental mode,which was triggered by the 2004 Sumatra-Andaman earthquake with a magni... This paper presents new estimations for all parameters(amplitude,frequency,quality factor,and initial phase)of the_(0)S_(0)Earth fundamental mode,which was triggered by the 2004 Sumatra-Andaman earthquake with a magnitude of Mw9.1.Sixteen records from the IGETS superconducting gravimeters have been analyzed.Using the maximum likelihood method algorithm,frequency,initial phase,and amplitude estimates have been acquired with remarkable accuracy.The values of frequency(814.6568±0.0002μHz)and quality factor(5455±17)obtained in this study differ slightly from those of the PREM model,and the amplitude variations qualitatively correspond to those of the SKS12WM13model.The estimated time delay between the onset of the earthquake and the excitation of the mode(290 s)is consistent with the moment tensor analysis from the USGS National Earthquake Information Center. 展开更多
关键词 Free oscillations of the Earth Normal mode Radial mode0s0 superconducting gravimeter sumatra-Andaman earthquake Lateral heterogeneities Maximal likelihood method
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Evaluation of NLLoc positioning method and seismogenic structure analysis of Luanzhou M_(S)4.3 earthquake
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作者 Zhang Yang Wang Xiao-Shan +3 位作者 Chen Ting Lv Guo-Jun Yu Hai-lin Chen Jun-lin 《Applied Geophysics》 2025年第3期729-738,894,895,共12页
NLLoc is a nonlinear search positioning method.In this study,we use simulated arrival time data to quantitatively evaluate the NLLoc method from three aspects:arrival time picking accuracy,station distribution,and vel... NLLoc is a nonlinear search positioning method.In this study,we use simulated arrival time data to quantitatively evaluate the NLLoc method from three aspects:arrival time picking accuracy,station distribution,and velocity model.The results show that the NLLoc method exhibits high positioning accuracy and stability in terms of arrival time picking accuracy and station distribution;however,it is sensitive to the velocity model.The positioning accuracy is higher when the velocity model is smaller than the true velocity.We combined absolute and relative positioning methods.First,we use the NLLoc method for absolute positioning of seismic data and then the double difference positioning method for relative positioning to obtain a more accurate relocation result.Furthermore,we used the combined method to locate the earthquake sequence after collecting dense seismic array data on the Luanzhou M_(S)4.3 earthquake that occurred on April 16,2021,in Hebei Province.By fitting the fault plane with the relocated earthquake sequences,the results show that the strike and dip angles of the seismogenic fault of the Luanzhou M_(S)4.3 earthquake are 208.5°and 85.6°,respectively.This indicates a high-dip angle fault with North-North-East strike and North-West dip directions.Furthermore,we infer that the seismogenic fault of the Luanzhou M_(S)4.3 earthquake is the Lulong fault. 展开更多
关键词 NLLoc method Combined multiple positioning methods Luanzhou M_(s)4.3 earthquake seismogenic structure Lulong fault
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An Automatic Damage Detection Method Based on Adaptive Theory-Assisted Reinforcement Learning
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作者 Chengwen Zhang Qing Chun Yijie Lin 《Engineering》 2025年第7期188-202,共15页
Current damage detection methods based on model updating and sensitivity Jacobian matrixes show a low convergence ratio and computational efficiency for online calculations.The aim of this paper is to construct a real... Current damage detection methods based on model updating and sensitivity Jacobian matrixes show a low convergence ratio and computational efficiency for online calculations.The aim of this paper is to construct a real-time automated damage detection method by developing a theory-assisted adaptive mutiagent twin delayed deep deterministic(TA2-MATD3)policy gradient algorithm.First,the theoretical framework of reinforcement-learning-driven damage detection is established.To address the disadvantages of traditional mutiagent twin delayed deep deterministic(MATD3)method,the theory-assisted mechanism and the adaptive experience playback mechanism are introduced.Moreover,a historical residential house built in 1889 was taken as an example,using its 12-month structural health monitoring data.TA2-MATD3 was compared with existing damage detection methods in terms of the convergence ratio,online computing efficiency,and damage detection accuracy.The results show that the computational efficiency of TA2-MATD3 is approximately 117–160 times that of the traditional methods.The convergence ratio of damage detection on the training set is approximately 97%,and that on the test set is in the range of 86.2%–91.9%.In addition,the main apparent damages found in the field survey were identified by TA2-MATD3.The results indicate that the proposed method can significantly improve the online computing efficiency and damage detection accuracy.This research can provide novel perspectives for the use of reinforcement learning methods to conduct damage detection in online structural health monitoring. 展开更多
关键词 Reinforcement learning Theory-assisted Damage detection Newton’s method Model updating Architectural heritage
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基于灰色系统理论的小样本P-S-N曲线拟合方法
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作者 张震 刘俭辉 +1 位作者 程玲玲 牛富超 《兰州理工大学学报》 北大核心 2026年第1期63-67,共5页
Bootstrap法在处理小样本疲劳试验数据时,只能在原始数据中进行抽样,所得数据信息有限.为此,引入灰色系统理论对小样本数据进行处理,建立数据的灰微分方程,并挖掘原始数据的隐藏关系,得到更多数据的潜在信息.首先,借助灰色系统理论处理... Bootstrap法在处理小样本疲劳试验数据时,只能在原始数据中进行抽样,所得数据信息有限.为此,引入灰色系统理论对小样本数据进行处理,建立数据的灰微分方程,并挖掘原始数据的隐藏关系,得到更多数据的潜在信息.首先,借助灰色系统理论处理原始数据;其次,通过Bootstrap法对已处理的数据进行抽样得到再生样本;最后,对再生样本进行处理得到小样本数据的P-S-N曲线.结果表明,与Bootstrap法相比,通过灰色Bootstrap法处理所得小样本P-S-N曲线精度更高. 展开更多
关键词 小样本 BOOTsTRAP法 灰色系统理论 P-s-N曲线
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基于改进Otsu算法的轴承图像阈值分割方法
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作者 赵宇航 吴超华 +2 位作者 王鑫 张晟琦 史晓亮 《机电工程》 北大核心 2026年第1期34-44,共11页
针对轴承装配后质检时,工业相机采集到的图像存在混合噪声和背光源过曝,导致图像分割精度不高、影响后续处理的问题,提出了一种基于多特征感知与贝叶斯优化的改进大津算法(Otsu)的轴承图像阈值分割方法。首先,在图像感知层面,读取、计... 针对轴承装配后质检时,工业相机采集到的图像存在混合噪声和背光源过曝,导致图像分割精度不高、影响后续处理的问题,提出了一种基于多特征感知与贝叶斯优化的改进大津算法(Otsu)的轴承图像阈值分割方法。首先,在图像感知层面,读取、计算了图像的灰度值、梯度幅值、局部二值模型并完成了储存,对三特征数据分别进行了归一化处理,加权融合了三特征数据,得到了轴承图像的加权融合图;然后,在计算效率层面,引入了贝叶斯优化与分块动态规划方法,替代了Otsu的穷举法;最后,结合感知方法与加速方法,得到了一种基于多特征感知与贝叶斯优化的改进Otsu算法(MFB-Otsu),并与其他阈值分割算法进行了性能对比实验。研究结果表明:与Otsu算法、自适应分割算法对比,MFB-Otsu算法在保留了轴承图像全局亮度分布的基础上,强化了外轮廓边缘,抑制了边缘噪声,输出图像边缘平滑,背景与前景彻底分离;在实测边缘提取中,边缘信息保留完整,噪点干扰率相较于Otsu降低了55%;在客观图像评价指标方面,该算法的分割准确率、交并比、F1值分别达到0.997、0.989、0.994,优于Otsu算法和自适应分割算法;在计算效率层面,相较于Otsu提高了12.9%。改进Otsu算法在轴承尺寸检测中表现出良好的通用性与稳定性,具有一定的工程应用价值。 展开更多
关键词 轴承装配 图像处理 图像分割 大津算法 多特征感知和贝叶斯优化 Otsu加速方法 三维度特征加权 分块动态优化
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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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Infinitely Many Negative Energy Solutions for Sublinear Schr¨odinger-Poisson System
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作者 CHENG Rong WU Xiao 《应用数学》 北大核心 2026年第2期564-572,共9页
In this paper,we consider a Schr¨odinger-Poisson system with sublinear nonlinearity.The growth of nonlinearity depends on potential function and a bounded function.We first obtain the existence of nontrivial solu... In this paper,we consider a Schr¨odinger-Poisson system with sublinear nonlinearity.The growth of nonlinearity depends on potential function and a bounded function.We first obtain the existence of nontrivial solution sequence with negative energy for the system via a variant Clark’s theorem.Then we get the asymptotical property of the solution sequence by L∞norm. 展开更多
关键词 Variational method schr¨odinger-Poisson system Multiple solutions Clark’s theorem ITERATION
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水热法制备Ti_(3)C_(2)@VS_(2)/S阴极材料及其在镁硫电池中的应用
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作者 葛佳音 寇准升 +3 位作者 闫晓燕 张晓华 赵新新 郭锦 《材料导报》 北大核心 2026年第4期1-7,共7页
为契合可持续发展能源需求,镁硫电池作为新型高能储能体系备受关注。本工作通过水热法成功构建了Ti_(3)C_(2)@VS_(2)/S复合材料作为镁硫电池的阴极,并通过电化学测试等方法系统评估了其性能。该材料在不同倍率条件下展现出优异的容量保... 为契合可持续发展能源需求,镁硫电池作为新型高能储能体系备受关注。本工作通过水热法成功构建了Ti_(3)C_(2)@VS_(2)/S复合材料作为镁硫电池的阴极,并通过电化学测试等方法系统评估了其性能。该材料在不同倍率条件下展现出优异的容量保持能力,在0.1C、0.2C、0.5C、1C、2C、5C下的初始放电比容量分别为1246.3 mAh·g^(-1)、1094.1 mAh·g^(-1)、978.1 mAh·g^(-1)、844.2 mAh·g^(-1)、568.3 mAh·g^(-1)、289.6 mAh·g^(-1);当倍率重新恢复至0.1C时,放电比容量仍稳定在1175.2 mAh·g^(-1),容量保持率达76.3%,且循环过程中容量衰减率也较低,为0.21%。本工作的结果为镁硫电池阴极材料的界面优化与动力学提升提供了重要实验依据。 展开更多
关键词 镁硫电池 Ti_(3)C_(2)Ti_(3)C_(2)@Vs_(2)/s 水热法 电化学性能
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大蒜中S-1-丙烯基-L-半胱氨酸的合成及生物学特性研究进展
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作者 田灵燕 王守锋 曾伟 《有机化学》 北大核心 2026年第1期74-86,共13页
S-1-丙烯基-L-半胱氨酸(S-1-propenyl-L-cysteine,S1PC)是一种天然存在于葱属植物中的含硫氨基酸,最早于20世纪60年代在大蒜制剂中被发现,也是老化大蒜提取物(Aged garlic extract,AGE)中的重要组分,在其发挥药理作用过程中扮演重要角色... S-1-丙烯基-L-半胱氨酸(S-1-propenyl-L-cysteine,S1PC)是一种天然存在于葱属植物中的含硫氨基酸,最早于20世纪60年代在大蒜制剂中被发现,也是老化大蒜提取物(Aged garlic extract,AGE)中的重要组分,在其发挥药理作用过程中扮演重要角色.自2016年起,已发现S1PC具有多种生物活性,包括抗高血压、抗炎和调节免疫特性.相较于完整大蒜,S1PC不仅气味更淡、毒性更低,还能规避消化不良、口臭等不良反应,对于期望获取大蒜健康益处的人群而言,是一种更具吸引力的选择.S1PC已被发现在高血压动物模型中有降低血压的作用,并且在体内、体外均有免疫调节作用.此外,S1PC具有抗炎作用,该特性有助于预防或管理与慢性炎症相关的疾病,如牙龈炎和动脉粥样硬化.基于上述发现,S1PC被认为与其同分异构体S-烯丙基-L-半胱氨酸(S-allyl-L-cysteine,SAC)一样,是AGE中另一种重要的、具有药理活性且安全的成分.综述了S1PC的理化性质等方面最新研究进展,并提出了其未来潜在的应用发展方向. 展开更多
关键词 s-1-丙烯基-L-半胱氨酸(s1PC) 葱属植物 理化性质 合成方法 生物活性 药代动力学
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A Self-Sacrifice Template Method to Produce FeS Encapsulated into N,S Co-Doped Carbon for Improved Lithium Storage Performance
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作者 Xu Liu Lan-Yun Yang +7 位作者 Li-Ting Zeng Yun Peng Chen-Xi Xu Lei Li Jia-Le Sun Yang-Yang Chen Liang Chen Zhao-Hui Hou 《Acta Metallurgica Sinica(English Letters)》 2025年第9期1637-1644,共8页
The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile ... The development of high-performance transition metal sulfide(TMS)/carbon composites to replace conventional graphite anode remains a critical challenge for advancing lithium-ion batteries(LIBs).In this study,a facile self-sacrifice template method is developed to prepare FeS encapsulated into N,S co-doped carbon(FeS/NSC)composite using melamine-cyanuric acid(MCA)supermolecule as a multifunctional template precursor.The function of MCA supermolecule for material synthesis is explored,revealing its special function as a dispersant,dopant and pore-forming agent.Furthermore,the effect of Fe source dosage on the morphology,structure and composition of the final products is explored.The resultant FeS/NSC-0.1(where 0.1 represents the mass of added Fe source)exhibits the most optimal proportion,characterized by a good dispersion status of FeS within the NSC matrix,effective N,S co-doping and ample porosity.Benefiting from these merits,the FeS/NSC-0.1 anode demonstrates significantly improved cycling stability and rate capability when compared to the counterparts.Undoubtedly,this work offers a universal method to produce advanced transition metal sulfide/carbon composite electrodes for energy storage and conversion systems. 展开更多
关键词 Lithium-ion batteries Lithium storage performance self-sacrifice template method Melamine-cyanuric acid(MCA)supermolecule Fes encapsulated into N s co-doped carbon(Fes/NsC)composite
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基于探测概率的不同类型S弯喷管隐身性能评估
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作者 郭霄 夏欣如 +3 位作者 李岳锋 文振华 吴梦珂 赵竹君 《科学技术与工程》 北大核心 2026年第8期3531-3542,共12页
现代化空战中,探测技术的飞速发展使得提高隐身性能成为高性能作战飞行器重点研发领域,航空发动机尾喷管是作战飞行器后向雷达散射特征信号的主要来源。针对传统尾喷管雷达隐身性能评估方法不够完全准确的问题,以单S弯、双S弯以及多维偏... 现代化空战中,探测技术的飞速发展使得提高隐身性能成为高性能作战飞行器重点研发领域,航空发动机尾喷管是作战飞行器后向雷达散射特征信号的主要来源。针对传统尾喷管雷达隐身性能评估方法不够完全准确的问题,以单S弯、双S弯以及多维偏转S弯三种不同S弯尾喷管为研究对象,使用迭代物理光学法计算分析得到喷管雷达散射截面积(radar cross section,RCS),基于单脉冲检测理论开展X、C波段下不同S弯喷管在俯仰、偏航探测面设定探测角范围内探测距离、探测概率分析。结果表明:在给定的雷达探测条件下,喷管的探测概率与探测距离与RCS起伏数据具有一定的相关性;给定信噪比的前提下,多维S弯喷管在两种探测面内的水平极化方式下具有最低的探测概率,在C波段内多维S弯的探测概率增大,双S弯喷管具有较低的探测概率;在给定探测概率前提下,多维S弯喷管在两个探测波段内具有最小的探测距离。 展开更多
关键词 雷达散射截面积(RCs) 探测概率 雷达检测理论 s弯喷管 迭代物理光学法
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带S形阻尼器矩形钢管混凝土柱-钢梁易修复节点弯矩-转角关系模型研究
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作者 李向民 杨瑞丰 +3 位作者 韩重庆 张富文 冷予冰 许清风 《工程力学》 北大核心 2026年第2期146-157,共12页
为预测带S形阻尼器的矩形钢管混凝土柱-钢梁易修复节点的弯矩-转角关系,提出基于初始转动刚度、抗弯承载力和形状系数的三参数幂函数模型。基于组件法推导了节点的初始转动刚度计算公式,基于塑性极限分析法推导了节点的抗弯承载力计算公... 为预测带S形阻尼器的矩形钢管混凝土柱-钢梁易修复节点的弯矩-转角关系,提出基于初始转动刚度、抗弯承载力和形状系数的三参数幂函数模型。基于组件法推导了节点的初始转动刚度计算公式,基于塑性极限分析法推导了节点的抗弯承载力计算公式,提出了S形阻尼器塑性极限状态时的受拉4铰机制和受压3铰机制。通过对节点试验和有限元参数分析结果的回归分析,得到节点抗弯承载力修正系数和形状系数。模拟带S形阻尼器易修复节点的实际应用,对带S形阻尼器易修复节点的钢框架-钢板剪力墙结构试件进行低周反复荷载试验和有限元参数分析,有限元分析模型中的梁、柱连接采用三参数模型。与节点试件的试验、有限元参数分析结果和结构试件的试验、有限元参数分析结果进行的对比表明,三参数模型对带S形阻尼器易修复节点弯矩-转角关系的模拟精度较高。 展开更多
关键词 钢管混凝土结构 弯矩-转角关系 组件法 s形阻尼器 初始转动刚度 抗弯承载力
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A CLASS OF NONLINEAR THERMO-PIEZOELECTRIC CONTACT PROBLEM WITH COULOMB'S LAW:EXISTENCE,UNIQUENESS AND CONVERGENCE
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作者 Jinxia CEN Abdelhadi HACHLAF 《Acta Mathematica Scientia》 2026年第1期255-274,共20页
In this paper,we study a comprehensive mathematical model describing the problem of frictional contact between a nonlinear thermo-piezoelectric body and a rigid foundation with electrically conductive effect,in which ... In this paper,we study a comprehensive mathematical model describing the problem of frictional contact between a nonlinear thermo-piezoelectric body and a rigid foundation with electrically conductive effect,in which the contact conditions are described by a Signorini’s condition and Coulomb’s friction law.We derive the variational form of the contact problem which is a mixed system formulated by variational inequalities and equalities.Then,we use standard results on mixed problems and the Banach fixed-point theorem to prove the existence and uniqueness of the solution to the contact problem.Moreover,we demonstrate the convergence of a penalty method for this contact problem under consideration.Finally,finite element method is applied to the penalty contact problem and a strong convergence theorem is obtained. 展开更多
关键词 thermo-piezoelectric material signorini’s condition mixed formulation existence and convergence penality method finite element method
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Influence of Martian environmental variables on methane partial pressure estimation
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作者 FengYi Chen Rui Li 《Earth and Planetary Physics》 2026年第2期315-325,共11页
Methane is considered a potential biosignature gas.The Mars Science Laboratory(MSL)Curiosity rover has observed seasonal variations in atmospheric methane within Gale Crater,suggesting possible microbial activity.The ... Methane is considered a potential biosignature gas.The Mars Science Laboratory(MSL)Curiosity rover has observed seasonal variations in atmospheric methane within Gale Crater,suggesting possible microbial activity.The origin of this methane could be either biological or abiotic or a combination of the two.Different physical mechanisms,involving distinct environmental variables,produce varying concentrations of methane.By analyzing the influence of various environmental variables on methane partial pressures and comparing differences between physical models and empirical measurements,we can better discern methane production mechanisms.This study investigates factors affecting methane cycling.We find that temperature and pressure strongly correlate with Martian atmospheric methane,while Ultraviolet(UV)radiation at the atmospheric boundary and surface UV radiation exhibit weaker correlations.Using Fuller’s method,we successfully reproduce the seasonal methane cycle in Gale Crater.Several potential physical models suggest that gas diffusion driven by variations in pressure and temperature within the shallow subsurface regolith may represent a primary mechanism determining methane concentrations observed in Gale Crater.However,errors in the pressure-dominated model cannot be neglected.As Curiosity enters its uphill exploration phase,we suggest that atmospheric pressure will play a significant role in predicting the methane concentrations that it will detect. 展开更多
关键词 METHANE Fuller’s method air pressure
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基于改进D-S证据理论的水下电子模块可靠性评估方法
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作者 安维峥 孙钦 +3 位作者 马婉蓉 张妍 杨卓 左信 《化工自动化及仪表》 2026年第1期54-60,共7页
针对水下电子模块可靠性数据的不确定性、低完备性和高冲突性问题,构建结合D-S证据理论与熵权法的水下电子模块可靠性评估方法。首先,基于D-S证据理论,构建了用于SEM可靠性评估的证据源与失效模式之间的基本信度分配矩阵。其次,针对证... 针对水下电子模块可靠性数据的不确定性、低完备性和高冲突性问题,构建结合D-S证据理论与熵权法的水下电子模块可靠性评估方法。首先,基于D-S证据理论,构建了用于SEM可靠性评估的证据源与失效模式之间的基本信度分配矩阵。其次,针对证据源数据的离散程度,利用熵权法改进基本信度分配矩阵,客观地确定各证据源的权重,降低了证据源冲突对可靠性评估造成的影响。最后,通过应用实例,表明SEM控制信号失效的概率在SEM所有失效模式中居于首位,因此在实际应用中需对该失效模式予以特别关注,为提升SEM可靠性提供了极具价值的参考。 展开更多
关键词 水下电子模块 失效模式 D-s证据理论 熵权法 可靠性评估
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基于主S-N曲线法的焊接接头疲劳强度评估程序开发及验证
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作者 周荣坤 王华健 +1 位作者 李瑞浩 聂春戈 《计算机辅助工程》 2026年第1期1-6,共6页
针对采用结构应力法评估焊接结构疲劳寿命时计算复杂和步骤繁琐的问题,采用MATLAB中的APP Designer模块开发基于结构应力法的焊缝疲劳寿命评估程序。根据相关文献中的3种焊接接头数据,采用本文程序完成结构应力计算,并将计算结果与fe-s... 针对采用结构应力法评估焊接结构疲劳寿命时计算复杂和步骤繁琐的问题,采用MATLAB中的APP Designer模块开发基于结构应力法的焊缝疲劳寿命评估程序。根据相关文献中的3种焊接接头数据,采用本文程序完成结构应力计算,并将计算结果与fe-safe软件计算结果进行对比,最大相对误差仅为1.48%。采用4种不同网格尺寸的搭接焊接接头进行计算,对比结构应力、von MISES应力和第一主应力的计算结果,验证结构应力计算的网格不敏感特性。程序计算寿命与试验寿命的对比验证本文程序的准确性和可靠性。 展开更多
关键词 结构应力 焊接接头 疲劳寿命 s-N曲线法 网格不敏感
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基于D-S证据理论与组合赋权的EPC模式建筑工程风险综合评价方法
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作者 陈莲 《齐齐哈尔大学学报(自然科学版)》 2026年第2期79-86,共8页
为了能够更全面、准确地反映工程面临的风险状况,避免单一信息源带来的片面性和误差,提出基于D-S证据理论与组合赋权的EPC模式建筑工程风险综合评价方法。构建涵盖场内与场外风险的EPC模式建筑工程风险评价指标体系;采用G1主观赋权法结... 为了能够更全面、准确地反映工程面临的风险状况,避免单一信息源带来的片面性和误差,提出基于D-S证据理论与组合赋权的EPC模式建筑工程风险综合评价方法。构建涵盖场内与场外风险的EPC模式建筑工程风险评价指标体系;采用G1主观赋权法结合专家经验排序指标重要性,利用COWA算子通过数据加权减少极端值干扰,通过博弈论实现多信息的组合赋权;引入D-S证据理论处理不确定性问题,通过基本概率分配函数和综合评价,融合多源信息,完成风险评估。结果表明,所提方法兼顾主观判断与客观数据特征,能更准确地反映风险状况,为EPC模式下的建筑工程风险管理提供科学依据。 展开更多
关键词 EPC模式 建筑工程 风险评价 D-s证据理论 G1方法 连续有序加权平均算子
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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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基于重排S-method的多分量辐射源信号分析方法 被引量:2
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作者 荣海娜 张葛祥 金炜东 《西南交通大学学报》 EI CSCD 北大核心 2009年第2期195-200,共6页
为实现多分量辐射源信号的有效检测和识别,提出了基于重排S-method(RSM)的多分量辐射源信号分析方法.针对Wigner-Ville分布交叉项严重和计算复杂度高的问题,采用RSM分析密集、交叠的辐射源信号,给出了其算法的硬件实现和计算复杂度分析... 为实现多分量辐射源信号的有效检测和识别,提出了基于重排S-method(RSM)的多分量辐射源信号分析方法.针对Wigner-Ville分布交叉项严重和计算复杂度高的问题,采用RSM分析密集、交叠的辐射源信号,给出了其算法的硬件实现和计算复杂度分析.该方法能处理线性和非线性调频信号,算法简单,易于实现.复杂体制多分量辐射源信号分析的实验结果表明,该方法能有效分析多分量辐射源信号,时频分辨率高,不受交叉项干扰,具有比Wigner-Ville分布和S-method更强的噪声抑制能力. 展开更多
关键词 时频分析 辐射源信号 多分量 重排s-method
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基于S-method的多分量雷达辐射源信号检测 被引量:2
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作者 荣海娜 张葛祥 金炜东 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2009年第1期174-179,共6页
针对传统时频方法在处理多分量雷达辐射源信号时存在交叉项,不能检测各分量信号时域参数,难以适应低信噪比环境的问题,提出一种基于S-method(SM)的多分量雷达辐射源信号检测新方法。该方法首先计算信号的SM时频分布,然后在时频面的基础... 针对传统时频方法在处理多分量雷达辐射源信号时存在交叉项,不能检测各分量信号时域参数,难以适应低信噪比环境的问题,提出一种基于S-method(SM)的多分量雷达辐射源信号检测新方法。该方法首先计算信号的SM时频分布,然后在时频面的基础上检测各信号分量的瞬时频率和脉冲起止时间。实验结果表明,该方法能处理线性及非线性调频信号、时频分辨率高且不受交叉项干扰,时域检测精度大于98.60%,频域检测精度大于99.48%,信噪比降低时仍然保持强检测能力。 展开更多
关键词 辐射源信号 时频分析 多分量 信号检测 s-method
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