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A Facile Photo-cross-linking Method for Polymer Gate Dielectrics and Their Applications in Fully Solution Processed Low Voltage Organic Field-effect Transistors on Plastic Substrate 被引量:1
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作者 Ying Liu Jia-Qing Zhao +4 位作者 Wen-Jian Sun Yu-Kun Huang Su-Jie Chen Xiao-Jun Guo Qing Zhang 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2018年第8期918-924,共7页
A simple and effective photochemical method was developed for cross-linking of polymer gate dielectrics. Laborious synthetic processes for functionalizing polymer dielectrics with photo-cross-linkable groups were avoi... A simple and effective photochemical method was developed for cross-linking of polymer gate dielectrics. Laborious synthetic processes for functionalizing polymer dielectrics with photo-cross-linkable groups were avoided. The photo-cross-linker, BBP-4, was added into host polymers by simple solution blending process, which was capable of abstracting hydrogen atoms from polymers containing active C--H groups upon exposure to ultraviolet (UV) radiation. The cross-linking can be completed with a relatively long wavelength UV light (365 nm). The approach has been applied to methacrylate and styrenic polymers such as commercial poly(methylmethacrylate) (PMMA), poly(iso-butylmethacrylate) (PiBMA) and poly(4-methylstyrene) (PMS). The cross-linked networks enhanced dielectric properties and solvent resistance of the thin films. The bottom-gate organic field-effect transistors (OFETs) through all solution processes on plastic substrate were fabricated. The OFET devices showed low voltage operation and steep subthreshold swing at relatively small gate dielectric capacitance. 展开更多
关键词 Organic field-effect transistors Solution processed Polymer dielectric cross-linking PHOTOCHEMISTRY
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STATISTICAL PROPERTY OF THRESHOLD-CROSSING FOR ZERO-MEAN-VALUED, NARROW-BANDED GAUSSIAN PROCESSES
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作者 HE Wu-zhou(贺五洲) +1 位作者 YUAN Ming-shun(苑明顺) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第6期701-710,共10页
Based on a comprehensive discussion of the calculation method for the threshold-crossing statistics of zero mean valued, narrow banded Gaussian processes of various practical engineering problems, including the thresh... Based on a comprehensive discussion of the calculation method for the threshold-crossing statistics of zero mean valued, narrow banded Gaussian processes of various practical engineering problems, including the threshold-crossing probability, average number of crossing events per unit time, mean threshold-crossing duration and amplitude, a new Simple numerical procedure is proposed for the efficient evaluation of mean threshold-crossing duration. A new dimensionless parameter, called the threshold-crossing intensity, is defined as a measure of the threshold-crossing severity, which is equal to the ratio of the product of average number of crossing events per unit time and mean threshold-crossing duration and amplitude over the threshold. It is found, by the calculation results for various combinations of stochastic processes and different thresholds, that the threshold-crossing intensity, irrelevant of the threshold and spectral density of the process, is dependent only on the threshold-crossing probability. 展开更多
关键词 stochastic process threshold-crossing statistical property
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Influence of process parameters on interracial tensile strength of crosswedge rolling of 42CrMo/Q235 laminated shafts
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作者 Wen-fei Peng Chao Yan +3 位作者 Xiao Zhang Xue-dao Shu Guang-xing Huang Dong-ming Xu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2018年第10期1003-1009,共7页
Through rolling experiments and interfacial tensile strength tests of cross-wedge rolled laminated shafts of 42CrMo/Q235 composites, the influence of process parameters, including forming angle, spreading angle, area ... Through rolling experiments and interfacial tensile strength tests of cross-wedge rolled laminated shafts of 42CrMo/Q235 composites, the influence of process parameters, including forming angle, spreading angle, area reduction, rolling temperature and core material diameter on the interfacial shear strength was analyzed. The results show that the sequence of process parameters in order of greatest influence on interfacial tensile strength was rolling temperature, area reduction, core material diameter, forming angle and spreading angle. At the interface of the combined materials, tensile strength decreased as forming angle and spreading angle increased, whereas the tensile strength first increased and then decreased as area reduction, rolling temperature and core material diameter increased. 展开更多
关键词 Laminated shaft process parameter Interfacial tensile strength cross-wedge rolling
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基于高阶次Cross Sensor处理的波束形成方法 被引量:6
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作者 郑恩明 黎远松 +2 位作者 余华兵 陈新华 孙长瑜 《振动与冲击》 EI CSCD 北大核心 2015年第24期12-19,共8页
为得到鲁棒性、高分辨波束形成,提出了一种高阶次Cross Sensor处理方法。该方法依据阵元间协方差矩阵同一斜对角线上不同元素具有相同相位差的特点,对协方差矩阵进行M阶次Cross Sensor处理后可虚拟出近(2^M-1)(N-1)个虚拟阵元(N为... 为得到鲁棒性、高分辨波束形成,提出了一种高阶次Cross Sensor处理方法。该方法依据阵元间协方差矩阵同一斜对角线上不同元素具有相同相位差的特点,对协方差矩阵进行M阶次Cross Sensor处理后可虚拟出近(2^M-1)(N-1)个虚拟阵元(N为原始阵元数)。虚拟阵元的增加可扩大线阵有效孔径,降低波束形成主瓣宽度,提高方位分辨率。在Cross Sensor处理过程中,该方法对协方差矩阵同一斜对角线上不同元素进行了叠加运算,可进一步削弱噪声对波束形成的影响,提高了波束形成鲁棒性。数值仿真和海上试验结果表明,该方法既能有效降低波束形成主瓣宽度,提高方位分辨率,又可削弱方位历程图干扰背景。相比已有的逆波束形成,该方法具有较好的方位分辨率;相比已有的基于AR模型的高分辨逆波束形成,该方法对最低门限信噪比的要求较低,方位估计均方误差较小。 展开更多
关键词 cross Sensor处理 波束形成 高分辨 鲁棒性
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轻量化广义互相关方法气体超声波流量计研究
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作者 邵昭 林志蒙 +2 位作者 陈倩 丁渊明 孔明 《应用声学》 北大核心 2026年第1期89-94,共6页
针对互相关法测量飞行时间差存在的问题,提出了一种轻量化广义互相关方法。为克服在处理大规模数据时互相关法计算量大的困难,通过阈值法找到回波的特征点,轻量化预处理截取关键回波信号进行运算。针对互相关函数峰值位置不明显而导致... 针对互相关法测量飞行时间差存在的问题,提出了一种轻量化广义互相关方法。为克服在处理大规模数据时互相关法计算量大的困难,通过阈值法找到回波的特征点,轻量化预处理截取关键回波信号进行运算。针对互相关函数峰值位置不明显而导致的精度问题,提出了对关键回波信号广义互相关与高频补零相结合的时间差估计方法,有效实现峰值锐化。飞行时间差通过计算上下游回波特征点序列的差值,并结合广义互相关方法得出的时间差来确定。进行流量实验研究,将上位机采集的回波信号数据使用该文算法进行处理,并与传统互相关法进行对比。结果表明,广义互相关方法计算超声回波飞行时间差具有较高的准确性,平均测量误差优于1.2%,重复性优于0.3%。 展开更多
关键词 气体超声流量计 信号处理 广义互相关法 飞行时间差 峰值检测
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Cross-Wedge Rolling of Shafts With an Eccentric Step 被引量:3
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作者 Zbigniew Pater 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2011年第6期26-30,共5页
A new concept for forming eccentric shafts on the basis of the cross-wedge rolling (CWR) process was presented. This concept was based on the application of special guides, which, by acting on a billet, lead to its ... A new concept for forming eccentric shafts on the basis of the cross-wedge rolling (CWR) process was presented. This concept was based on the application of special guides, which, by acting on a billet, lead to its controlled movement in the vertical direction. This movement made possible eccentric cutting of tools into the billet. FEM calculations and experimental rolling tests clearly confirmed the effectiveness of the proposed forming method. 展开更多
关键词 cross-wedge rolling process eccentric shaft FEM
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Autonomous process collaboration framework for C4ISR system interoperation 被引量:5
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作者 Lin Yang Minggang Yu Qingchao Dong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2017年第6期1098-1113,共16页
Interoperability plays an important role in the joint command, control, communication, computer, intelligence, surveillance, reconnaissance(C4 ISR) operations. Coordinating and integrating operational processes to ful... Interoperability plays an important role in the joint command, control, communication, computer, intelligence, surveillance, reconnaissance(C4 ISR) operations. Coordinating and integrating operational processes to fulfill a common mission are challenged by the ever-changing battlefield and hence requires a cross-organizational process management that produces an autonomous, flexible and adaptable architecture for collaborative process evolution. The traditional business process collaboration pattern is based on the predefined "public-view" perspective and cannot meet the requirement of the joint task operations. This paper proposes a flexible visibility control mechanism and a dynamic collaboration framework for modeling and generating collaborative processes. The mechanism allows collaborators to define a set of visibility rules to generate different views of the private processes for different collaborations, which gives a great flexibility for the collaboration initiator to decide on an appropriate collaboration pattern. The framework supports collaborators to dynamically and recursively add a new process or even a new organization to an existing collaboration. Moreover, a formal representation of the processes and a set of generation algorithms are provided to consolidate the proposed theory. 展开更多
关键词 cross-organizational collaboration INTEROPERABILITY collaborative process joint operations
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RESEARCH ON THE ALGORITHM OF BINARY IMAGE CROSS-CORRELATION FOR UNSTEADY FLOW FIELD MEASUREMENT 被引量:2
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作者 阮晓东 宋向群 YamamotoFujio 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 1999年第1期32-38,共7页
The algorithm of Binary Image Cross-Correlation (BICC) was developed to measure the unsteady flow field. A vortex flow field was used to test the algorithm by numerical simulation. The results show that BICC is an e... The algorithm of Binary Image Cross-Correlation (BICC) was developed to measure the unsteady flow field. A vortex flow field was used to test the algorithm by numerical simulation. The results show that BICC is an effective algorithm for particle identification from consecutive images, the accurate velocity vector field can be obtained. The real velocity field in a valve chamber was measured by BICC in this study. From the full-field velocity information, the pressure and vorticity fields were also extracted by post-processing. (Edited author abstract) 6 Refs. 展开更多
关键词 PIV cross-CORRELATION particle identification POST-processING
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Detrended cross-correlation analysis of electroencephalogram 被引量:5
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作者 Wang Jun Zhao Da-Qing 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第2期577-580,共4页
In the paper we use detrended cross-correlation analysis (DCCA) to study the electroencephalograms of healthy young subjects and healthy old subjects. It is found that the cross-correlation between different leads o... In the paper we use detrended cross-correlation analysis (DCCA) to study the electroencephalograms of healthy young subjects and healthy old subjects. It is found that the cross-correlation between different leads of a healthy young subject is larger than that of a healthy old subject. It was shown that the cross-correlation relationship decreases with the aging process and the phenomenon can help to diagnose whether the subject's brain function is healthy or not. 展开更多
关键词 detrended cross-correlation analysis ELECTROENCEPHALOGRAM brain function aging process
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CROSS-SPECTRAL MOMENT AND SVD METHODS ESTIMATING THE PARAMETERS OF CLOSE SINUSOIDS IN COLORED NOISE
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作者 石要武 戴逸松 宫文斌 《Journal of Electronics(China)》 1995年第2期142-150,共9页
The cross-spectral estimation methods are efficient in estimating the parameters of sinusoidal signals embedded in colored noise. But up to now, only FPT and cross-periodogram methods are used in this field, the moder... The cross-spectral estimation methods are efficient in estimating the parameters of sinusoidal signals embedded in colored noise. But up to now, only FPT and cross-periodogram methods are used in this field, the modern auto-spectral estimation method is introduced into cross-spectral estimation in this paper, meanwhile the cross-correlation based Yule-Walker equation is proposed theoretically and the moment and singular-value decomposition (SVD)) algorithms for cross-spectral estimation have been developed. Finally, a numerical example is given for comparing the presented methods with the well-known Cadzow’s SVD method. 展开更多
关键词 Signal processing cross-spectral estimation COLORED noise
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A Scalable Method for Cross-Platform Merging of SNP Array Datasets
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作者 Peikai Chen Y. S. Hung 《Engineering(科研)》 2013年第10期502-508,共7页
Single nucleotide polymorphism (SNP) array is a recently developed biotechnology that is extensively used in the study of cancer genomes. The various available platforms make cross-study validations/comparisons diffic... Single nucleotide polymorphism (SNP) array is a recently developed biotechnology that is extensively used in the study of cancer genomes. The various available platforms make cross-study validations/comparisons difficult. Meanwhile, sample sizes of the studies are fast increasing, which poses a heavy computational burden to even the fastest PC.Here, we describe a novel method that can generate a platform-independent dataset given SNP arrays from multiple platforms. It extracts the common probesets from individual platforms, and performs cross-platform normalizations and summari-zations based on these probesets. Since different platforms may have different numbers of probes per probeset (PPP), the above steps produce preprocessed signals with different noise levels for the platforms. To handle this problem, we adopt a platform-dependent smoothing strategy, and produce a preprocessed dataset that demonstrates uniform noise levels for individual samples.To increase the scalability of the method to a large number of samples, we devised an algorithm that split the samples into multiple tasks, and probesets into multiple segments before submitting to a parallel computing facility. This scheme results in a drastically reduced computation time and increased ability to process ultra-large sample sizes and arrays. 展开更多
关键词 SNP ARRAY SCALABLE processING cross-PLATFORM
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Improving reservoir volumetric estimations in petroleum resource assessment using discovery process models 被引量:2
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作者 Osadetz Kirk G. 《Petroleum Science》 SCIE CAS CSCD 2009年第2期105-118,共14页
The reservoir volumetric approach represents a widely accepted, but flawed method of petroleum play resource calculation. In this paper, we propose a combination of techniques that can improve the applicability and qu... The reservoir volumetric approach represents a widely accepted, but flawed method of petroleum play resource calculation. In this paper, we propose a combination of techniques that can improve the applicability and quality of the resource estimation. These techniques include: 1) the use of the Multivariate Discovery Process model (MDP) to derive unbiased distribution parameters of reservoir volumetric variables and to reveal correlations among the variables; 2) the use of the Geo-anchored method to estimate simultaneously the number of oil and gas pools in the same play; and 3) the crossvalidation of assessment results from different methods. These techniques are illustrated by using an example of crude oil and natural gas resource assessment of the Sverdrup Basin, Canadian Archipelago. The example shows that when direct volumetric measurements of the untested prospects are not available, the MDP model can help derive unbiased estimates of the distribution parameters by using information from the discovered oil and gas accumulations. It also shows that an estimation of the number of oil and gas accumulations and associated size ranges from a discovery process model can provide an alternative and efficient approach when inadequate geological data hinder the estimation. Cross-examination of assessment results derived using different methods allows one to focus on and analyze the causes for the major differences, thus providing a more reliable assessment outcome. 展开更多
关键词 Multivariate Discovery process model sampling bias correction cross-validation Geoanchored method
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3-D RECONSTRUCTION OF SHAPE AND STRUCTURE FOR THE SPACE OBJECT FROM SERIAL CROSS-SECTIONS
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作者 张立坚 曹有江 沈兰荪 《Journal of Electronics(China)》 1991年第4期367-372,共6页
A new method for reconstructing a 3-dimensional object from serial cross-sectionsis presented in this paper.The method is based on the principle of sampling and considersevery point in cross-sections as a sampling poi... A new method for reconstructing a 3-dimensional object from serial cross-sectionsis presented in this paper.The method is based on the principle of sampling and considersevery point in cross-sections as a sampling point and performs the interpolating of nonlinearfunction with these sampling points.Compared with other methods,this method has manyadvantages such as higher precision and fewer requested known sampling points.The result ofreconstruction with this method is an“entity”which involves the exterior shape and interiorconstruction information of the object simultaneously. 展开更多
关键词 DIGITAL IMAGE processING SERIAL cross-SECTION 3-Dimensional reconstructing
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数字经济下创新驱动创业过程中认知、行为和能力的跨层面作用机制--基于三一集团的案例研究 被引量:5
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作者 蔡莉 杨亚倩 +1 位作者 詹天悦 盛乃珩 《南开管理评论》 北大核心 2025年第5期173-184,共12页
随着数字经济的蓬勃发展,创新驱动创业实践不断涌现。然而,实践走在理论前面,现有研究仍处于概念探讨阶段,鲜有学者从跨层面角度对数字经济下创新驱动创业的过程机理深入探究。本文以三一集团为研究案例,从意义建构视角深入挖掘数字经... 随着数字经济的蓬勃发展,创新驱动创业实践不断涌现。然而,实践走在理论前面,现有研究仍处于概念探讨阶段,鲜有学者从跨层面角度对数字经济下创新驱动创业的过程机理深入探究。本文以三一集团为研究案例,从意义建构视角深入挖掘数字经济下创新驱动创业过程中认知的跨层面转化机制。研究发现:认知跨层面转化的聚焦点在创新驱动创业过程发展的不同阶段有所差异;认知、行为和能力互动是创新驱动创业过程中认知层面不断跨越的深层次机制;数字经济下创新驱动创业过程中认知、行为、能力及其互动关系呈现独特性。研究结论对于揭示数字经济下创新驱动创业的过程机理具有重要的理论价值,也对数字经济时代我国企业创新驱动创业活动的开展具有指导意义。 展开更多
关键词 创新驱动创业 跨层研究 过程机理 意义建构 数字经济
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Efficient Simulation of Stationary Multivariate Gaussian Random Fields with Given Cross-Covariance
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作者 Jakob Teichmann Karl-Gerald van den Boogaart 《Applied Mathematics》 2016年第17期2183-2194,共12页
The present paper introduces a new approach to simulate any stationary multivariate Gaussian random field whose cross-covariances are predefined continuous and integrable functions. Such a field is given by convolutio... The present paper introduces a new approach to simulate any stationary multivariate Gaussian random field whose cross-covariances are predefined continuous and integrable functions. Such a field is given by convolution of a vector of univariate random fields and a functional matrix which is derived by Cholesky decomposition of the Fourier transform of the predefined cross-covariance matrix. In contrast to common methods, no restrictive model for the cross-covariance is needed. It is stationary and can also be reduced to the isotropic case. The computational effort is very low since fast Fourier transform can be used for simulation. As will be shown the algorithm is computationally faster than a recently published spectral turning bands model. The applicability is demonstrated using a common numerical example with varied spatial correlation structure. The model was developed to support simulation algorithms for mineral microstructures in geoscience. 展开更多
关键词 Image processing CONVOLUTION cross-COVARIANCE Cholesky Decomposition Fourier Transformation
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基于CAE技术的ABS矿用检测仪外壳成型质量研究
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作者 费然 李海军 张江城 《塑料工业》 北大核心 2025年第4期97-105,115,共10页
本研究旨在优化矿用传感器外壳的注塑成型工艺,以减少翘曲变形,提高制件的成型质量和尺寸精度。通过UG 12.0软件对矿用检测仪外壳构建了三维模型,再通过Moldflow软件对ABS材料进行注塑模拟分析,结合双域Tait模型和Cross-WLF模型,对丙烯... 本研究旨在优化矿用传感器外壳的注塑成型工艺,以减少翘曲变形,提高制件的成型质量和尺寸精度。通过UG 12.0软件对矿用检测仪外壳构建了三维模型,再通过Moldflow软件对ABS材料进行注塑模拟分析,结合双域Tait模型和Cross-WLF模型,对丙烯腈-丁二烯-苯乙烯共聚物(ABS)的注塑成型过程进行数学建模和仿真分析,确定了最佳的注塑成型工艺参数。结果表明,最佳的注塑成型工艺参数是:熔体温度为226.8℃,注射压力为20 MPa、保压压力为20 MPa,冷却时间为64 s。优化后的工艺参数显著减少了制件的翘曲变形量,上盖和下底制件的翘曲变形量分别降低了27.0%和52.5%。此外,气穴和熔接线的分布更加均匀,缩痕指数也显著降低,说明优化后的工艺参数能够有效提升制件的成型质量和尺寸精度。通过实际注塑成型试模,验证了优化工艺的可行性和有效性。本文结果不仅验证了所采用模型的有效性,也为矿用检测仪外壳ABS材料的注塑成型工艺提供了科学的理论依据和实践指导。 展开更多
关键词 矿用检测仪外壳 双域Tait模型 cross-WLF模型 工艺优化 MOLDFLOW
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一种结合有监督分类器和MEWMA的控制图
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作者 周茂袁 邱静 +1 位作者 周茂凯 钱琨 《应用概率统计》 北大核心 2025年第1期28-42,共15页
在过程监控中,使用现代工业系统中的变量进行准确有效的监控诊断仍然是一个具有挑战性的任务.本文以多元指数加权移动平均(MEWMA)策略结合一种有监督分类器(“one plus epsilon”,简称OPE分类器),提出OPE-MEWMA控制图.在考虑不同模型、... 在过程监控中,使用现代工业系统中的变量进行准确有效的监控诊断仍然是一个具有挑战性的任务.本文以多元指数加权移动平均(MEWMA)策略结合一种有监督分类器(“one plus epsilon”,简称OPE分类器),提出OPE-MEWMA控制图.在考虑不同模型、偏移模式和偏移大小的情况下,探究了控制图对均值偏移的检测能力,通过比较平均运行长度等多个指标衡量控制图的性能表现.仿真结果表明,所开发的OPE-MEWMA控制图能够快速检测到均值偏移,灵敏度较高. 展开更多
关键词 统计过程控制 多元指数加权移动平均控制图 交叉熵损失 蒙特卡洛模拟
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长江中游松滋河鱼类早期资源与水文情势的相关性研究 被引量:2
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作者 刘超 魏秘 +3 位作者 李德旺 李嗣新 胡俊 鲁程鹏 《长江流域资源与环境》 北大核心 2025年第5期993-1001,共9页
为了解长江中游松滋河鱼类早期资源的总体状况,并探讨水文过程对鱼类早期资源的影响,于2022年5月至7月在松滋河江段开展了鱼类早期资源调查。调查结果显示,鱼类种群在6月底集中产卵,进入7月后鱼卵数量减少,而鱼苗数量显著增加。通过交... 为了解长江中游松滋河鱼类早期资源的总体状况,并探讨水文过程对鱼类早期资源的影响,于2022年5月至7月在松滋河江段开展了鱼类早期资源调查。调查结果显示,鱼类种群在6月底集中产卵,进入7月后鱼卵数量减少,而鱼苗数量显著增加。通过交叉分析法研究水文过程对鱼类产卵的影响,发现鱼卵数量的变化提前于流量变化0~2 d;鱼苗数量与流量呈显著滞后相关(3~7 d);在整个调查周期内,鱼卵数量变化与水温无显著滞后相关性,而鱼苗数量变化与水温存在显著滞后相关性。结合格兰杰因果分析法探究水文过程与鱼类产卵的因果关系,发现流量和水温与鱼卵数量变化均无显著因果关系,而与鱼苗数量变化存在显著因果关系。具体来说,提前3~7 d的流量与鱼苗数量变化相关性较强,提前2 d的水温与鱼苗数量存在显著因果关系。进一步结合同期三峡水库的调度过程,分析显示,三峡生态调度是松滋河鱼类早期资源变化的重要原因。三峡生态调度不仅有助于长江鱼类的繁殖产卵,还通过松滋河对洞庭湖鱼类资源的补充起到了积极作用。 展开更多
关键词 鱼类早期资源 水文过程 交叉相关性 格兰杰因果关系
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基于情景构建和推演的终端区管制系统安全风险
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作者 张兆宁 何雅晴 《科学技术与工程》 北大核心 2025年第33期14496-14506,共11页
终端区是民航运输中极易发生不安全事件的区域,终端区管制系统作为空中交通管制系统中至关重要的一部分,对其运行过程进行安全风险研究至关重要。针对终端区管制系统安全风险耦合性强、传统分析方法难以量化风险之间交互效应的问题,提... 终端区是民航运输中极易发生不安全事件的区域,终端区管制系统作为空中交通管制系统中至关重要的一部分,对其运行过程进行安全风险研究至关重要。针对终端区管制系统安全风险耦合性强、传统分析方法难以量化风险之间交互效应的问题,提出一种将系统理论过程分析(system-theoretic process analysis,STPA)与交叉影响分析-解释结构模型(cross impact analysis and interpretive structure model,CIA-ISM)相结合的风险分析方法。首先利用STPA识别出系统中的20个安全风险因素;其次,采用皮尔逊(Pearson)相关系数法替代传统德尔菲法以消除主观偏差,结合200起历史事故数据量化风险因素间的影响强度,构建交叉影响矩阵;最后,通过ISM模型划分风险层级并推演终端区管制系统运行时的不安全状态对事故发生概率的影响程度,从而分析终端区管制系统的关键风险因素。并以青岛终端区管制系统为例,通过情景推演揭示多因素耦合下发生事故概率趋近1的动态机制,验证该模型的有效性。结果表明,管制班组配合不当等5类直接致因对不安全事件影响概率达84%,管制班组配合不当,和相邻管制室的协调、移交、配合有问题,管制员公布情报数据有误是对终端区管制系统安全运行影响最大的3个直接风险致因。 展开更多
关键词 终端区管制 系统理论过程分析 交叉影响分析 解释结构模型 风险因素相关关系 情景构建与推演
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(e,2e) triple-differential cross sections for Ag^+ (4p, 4s) in coplanar symmetric geometry
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作者 周丽霞 燕友果 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期204-207,共4页
The (e, 2e) triple-differential cross sections of Ag+ (4p, 4s) are calculated based on the three-body distorted-wave Born approximation considering post-collision interaction in coplanar symmetric geometry. The e... The (e, 2e) triple-differential cross sections of Ag+ (4p, 4s) are calculated based on the three-body distorted-wave Born approximation considering post-collision interaction in coplanar symmetric geometry. The energy of the outgoing electron is set to be 50, 70, 100, 200, 300,500, 700, and 1000 eV, and the intensity and splitting of forward and backward peaks are discussed in detail. Some new structures are observed around 15° and 85° for 4p and 4s orbitals. Structures in triple-differential cross sections at 15° are reported for the first time. A double-binary collision is proposed to explain the formation of such structures. The structures at 85° are also considered as the result of one kind of double-binary collision. 展开更多
关键词 (e 2e) process distorted-wave Born approximation triple-differential cross section coplanar symmetric geometry
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