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关键词

严格雪崩准则 3

BP算法 2

Bent函数 2

Walsh循环谱 2

主成分 2

功能 2

相关性分析 2

自相关函数 2

2-基展开 1

2型糖尿病 1

3S 1

AR模型 1

BP神经网络 1

B样条函数 1

CAESAR竞赛；认证加密算法；分组密码；序列密码；哈希函数；安全性评估 1

Chrestenson谱 1

Gompertz分布 1

Griewank；双尺度结构；多尺度量子谐振子算法；量子隧道效应 1

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Correlation analysis of couple optical paths for micro stereovision with stereo light microscope

WANG Yuezong, LI Desheng, YU Yaping

《机械工程前沿（英文）》 2007年第2卷第3期页码 288-292 doi: 10.1007/s11465-007-0050-6

摘要： A micro stereovision system with a stereo light microscope (SLM) has been applied in micromanipulation systems. There is a coupling connection between two optical paths of a stereo light microscope. The coupling intension corresponds with two factors: the structure of an SLM and the position of an object point in the view of an SLM. In this paper, a correlation function is proposed to describe the coupling intension between the couple optical paths of an SLM. The quantified results are applied to the error analysis of the imaging model. Experiments show that the correlation of the optical paths of a common main objective of stereo light microscope (CMO-SLM) is little more than that of a G-SLM, and the error must be considered when a pinhole imaging model is used to analyze its correlation.

关键词： intension micromanipulation correlation function objective quantified

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类差分平衡函数的性质及其应用

张文英,李世取

《中国工程科学》 2004年第6卷第3期页码 45-52

摘要：

定义了布尔函数的类差分和类差分平衡函数，研究了类差分平衡函数的密码学性质以及构造方法。作为类差分平衡函数的应用，给出了〓上逻辑函数是完全非线性函数的充要条件，并在首先分析得到所有四元类差分平衡函数的基础上，编程搜索出〓上所有的完全非线性函数。

关键词： Bent函数完全非线性函数 2-基展开类差分类自相关函数类差分平衡函数

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与特定密码函数线性等价的布尔函数谱和自相关特征

杨锐,曾本胜,李世取

《中国工程科学》 2005年第7卷第11期页码 60-65

摘要：

对线性等价意义下2个布尔函数的密码学性质的异同做了进一步的分析，得到了一个布尔函数线性等价于某个具有m阶相关免疫性的布尔函数的充分必要条件和线性等价于某个满足k次扩散准则的布尔函数的充分必要条件，在线性等价意义上，给出了由不具有相关免疫性且不满足扩散准则的布尔函数，构造既具有相关免疫性、也满足扩散准则的布尔函数的实例。

关键词：线性等价 Walsh循环谱自相关函数相关免疫性扩散准则 SAC

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满足k阶严格雪崩准则的多值逻辑函数的谱特征

郭锦辉,李世取

《中国工程科学》 2005年第7卷第12期页码 45-48

摘要：

给出了剩余类环Z_m上逻辑函数的k阶严格雪崩准则(SAC)的概念, 用概率方法证明了m值逻辑函数满足高阶严格雪崩准则时一定满足低阶严格雪崩准则, 并借助Chrestenson谱给出了m值逻辑函数满足k阶严格雪崩准则的一个充分必要条件。

关键词： m值逻辑函数 Chrestenson谱自相关函数严格雪崩准则

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Image automatic mosaics based on contour phase correlation

ZHANG Jing, HU Zhiping, OU Zongying, LIU Zhitai

《机械工程前沿（英文）》 2007年第2卷第2期页码 228-234 doi: 10.1007/s11465-007-0040-8

摘要： The image planar mosaics is studied, and an image automatic mosaics algorithm on the basis of contour phase correlation is proposed in this paper. To begin with, by taking into account mere translations and rotations between images, a contour phase correlation algorithm is used to realize the preliminary alignments of images, and the initial projective transformation matrices are obtained. Then, an optimization algorithm is used to optimize the initial projective transformation matrices, and complete the precise image mosaics. The contour phase correlation is an improvement on the conventional phase correlation in two aspects: First, the contours of images are extracted, and the phase correlation is applied to the contours of images instead of the whole original images; Second, when there are multiple peak values approximate to the maximum peak value in the ? function array, their corresponding translations can be regarded as candidate translations and calculated separately, and the best translation can be determined by the optimization of conformability of two images in the overlapping area. The running results show that the proposed algorithm can consistently yield high-quality mosaics, even in the cases of poor or differential lighting conditions, existences of minor rotations, and other complicated displacements between images.

关键词： function conventional multiple algorithm correlation algorithm

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选择逻辑函数的密码学性质

梁增,李世取

《中国工程科学》 2005年第7卷第7期页码 50-54

摘要：

通过计算选择逻辑函数的Walsh循环谱和自相关函数，系统分析了选择逻辑函数的密码学性质。所得结论表明选择逻辑函数在变元个数较大的情况下具有理想的稳定性，能够抵抗最佳仿射（BAA）攻击，但是其“扩散”特性不够理想，在一定意义下不能有效地抗击差分攻击。讨论了与选择逻辑函数线性等价意义下满足严格雪崩准则或具有相关免疫性的逻辑函数构造问题。

关键词：选择逻辑函数 Walsh循环谱自相关函数严格雪崩准则相关免疫概率表示式

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Digital image correlation-based structural state detection through deep learning

《结构与土木工程前沿（英文）》 2022年第16卷第1期页码 45-56 doi: 10.1007/s11709-021-0777-x

摘要： This paper presents a new approach for automatical classification of structural state through deep learning. In this work, a Convolutional Neural Network (CNN) was designed to fuse both the feature extraction and classification blocks into an intelligent and compact learning system and detect the structural state of a steel frame; the input was a series of vibration signals, and the output was a structural state. The digital image correlation (DIC) technology was utilized to collect vibration information of an actual steel frame, and subsequently, the raw signals, without further pre-processing, were directly utilized as the CNN samples. The results show that CNN can achieve 99% classification accuracy for the research model. Besides, compared with the backpropagation neural network (BPNN), the CNN had an accuracy similar to that of the BPNN, but it only consumes 19% of the training time. The outputs of the convolution and pooling layers were visually displayed and discussed as well. It is demonstrated that: 1) the CNN can extract the structural state information from the vibration signals and classify them; 2) the detection and computational performance of the CNN for the incomplete data are better than that of the BPNN; 3) the CNN has better anti-noise ability.

关键词： structural state detection deep learning digital image correlation vibration signal steel frame

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Diagnosis method based on wavelet coefficient scale relativity correlation dimension for fault

GU Junjie, TIAN Jin, PENG Xuezhi

《能源前沿（英文）》 2008年第2卷第2期页码 164-168 doi: 10.1007/s11708-008-0031-4

摘要： Correlation dimension as a tool to describe machinery condition is introduced. Vibration signals of the fan under different working conditions are analyzed using a threshold filtering algorithm based on the region relativity of the wavelet coefficients for reducing noise. The result shows that the characteristics of the signal could be preserved completely. The correlation dimension is able to identify conditions of the fan with faults compared with the normal condition, thereby providing an effective technology for condition monitoring and fault diagnosis of mechanical equipment.

关键词： effective technology monitoring mechanical equipment relativity Correlation

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Reliability analysis of urban gas transmission and distribution system based on FMEA and correlation

Su LI,Weiguo ZHOU

《能源前沿（英文）》 2014年第8卷第4期页码 443-448 doi: 10.1007/s11708-014-0336-4

摘要： In order to improve the safety management of urban gas transmission and distribution system, failure mode and effects analysis (FMEA) was used to construct the reliability analysis system of the pipeline network. To solve the problem of subjectivity and uncertainty of the multi-expert decision making, the correlation operator was introduced into the calculation of the risk priority number (RPN). Using FMEA along with weight analysis and expert investigation approach, the FMEA evaluation table was given, including five failure modes, risk priority numbers, failure causes and effects, as well as corrective actions. The results show that correlation operator can directly process the linguistic terms and quantify the priority of the risks.

关键词： gas transmission and distribution system risk evaluation reliability analysis failure mode and effects analysis (FMEA) correlation operator

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Measurement and correlation of the solid-liquid equilibrium of 2-(

Yanhong SUN, Zhiyong LI, Chuang XIE, Wei CHEN, Cui ZHANG

《化学科学与工程前沿（英文）》 2013年第7卷第1期页码 110-115 doi: 10.1007/s11705-013-1316-7

摘要： In this work, the enthalpy of fusion and melting points of 2-( -butyl)-5-methylphenol (2B5MP) and 2-( -butyl)-4-methylphenol (2B4MP) were measured by differential scanning calorimetry (DSC). The binary solid-liquid equilibrium (SLE) of both compounds were predicted by integrated computer aided system (ICAS) and measured by DSC. The corresponding eutectic molar composition is 0.6998 and the eutectic temperature is 281.96 K. The quasi-static heat capacities of 2B5MP and 2B4MP were evaluated by stochastic temperature modulation DSC technique (TOPEM). The SLE experimental data were correlated using the Margules, Wilson, and non-random two liquid (NRTL) equations and a good agreement between measurement and calculation could be obtained.

关键词： solid-liquid equilibrium (SLE) eutectic integrated computer aided system (ICAS) TOPEM correlation

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Deformation field and crack analyses of concrete using digital image correlation method

Yijie HUANG, Xujia HE, Qing WANG, Jianzhuang XIAO

《结构与土木工程前沿（英文）》 2019年第13卷第5期页码 1183-1199 doi: 10.1007/s11709-019-0545-3

摘要： The study on the deformation distribution and crack propagation of concrete under axial compression was conducted by the digital image correlation (DIC) method. The main parameter in this test is the water-cement ( / ) ratio. The novel analysis process and numerical program for DIC method were established. The displacements and strains of coarse aggregate, and cement mortar and interface transition zone (ITZ) were obtained and verified by experimental results. It was found that the axial displacement distributed non-uniformly during the loading stage, and the axial displacements of ITZs and cement mortar were larger than that of coarse aggregates before the occurrence of macro-cracks. The effect of / on the horizontal displacement was not obvious. Test results also showed that the transverse and shear deformation concentration areas (DCAs) were formed when stress reached 30%–40% of the peak stress. The transverse and shear DCAs crossed the cement mortar, and ITZs and coarse aggregates. However, the axial DCA mainly surrounded the coarse aggregate. Generally, the higher / was, the more size and number of DCAs were. The crack propagations of specimens varied with the variation of / . The micro-crack of concrete mainly initiated in the ITZs, irrespective of the / . The number and distribution range of cracks in concrete with high / were larger than those of cracks in specimen adopting low / . However, the value and width of cracks in high / specimen were relatively small. The / had an obvious effect on the characteristics of concrete deterioration. Finally, the characteristics of crack was also evaluated by comparing the calculated results.

关键词： deformation filed distribution crack development digital image correlation method mechanical properties water-cement ratio characteristics of deformation and crack

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Free radical scavenging window of infertile patients with polycystic ovary syndrome: correlation with

null

《医学前沿（英文）》 2017年第11卷第2期页码 247-252 doi: 10.1007/s11684-017-0519-6

摘要：

The activity of free radicals in follicular fluid was related to ovarian responsiveness, in vitro fertilization (IVF), and embryo transfer success rate. However, studies analyzing the relationship between the free radical scavenging capacity and embryo quality of infertile women with polycystic ovarian syndrome (PCOS) were lacking. The aim of this study was to evaluate the relationship between the free radical scavenging window of women with PCOS and their embryo quality. The free radical scavenging capacity of follicular fluid from women with PCOS was determined by a,a-diphenyl-b-picrylhydrazyl (DPPH), 2,2-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) assay, superoxide radical, and reactive oxygen species (ROS) assay. In the DPPH and ROS assays, the follicular fluid from grades I and II embryos was significantly higher than the follicular fluid from grades III and IV embryos. The lower control limit of DPPH radical scavenging capacity and upper control limit of ROS level were 13.2% and 109.0 cps, respectively. The calculated lower control limit and upper control limit were further confirmed in the follicular fluid of embryos of all grades. These cut-off values of free radical scavenging activity of follicular fluid could assist embryologists in choosing the development of embryos in PCOS patients undergoing IVF.

关键词： in vitro fertilization PCOS free radical embryo quality

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Characteristic and correlation analysis of influent and energy consumption of wastewater treatment plants

Luxi Zou, Huaibo Li, Shuo Wang, Kaikai Zheng, Yan Wang, Guocheng Du, Ji Li

《环境科学与工程前沿（英文）》 2019年第13卷第6期 doi: 10.1007/s11783-019-1167-7

摘要： Poor biodegradability and insufficient carbon source are discovered from influent. Influent indices presented positively normal distribution or skewed distribution. Average energy consumption of WWTPs in Taihu Basin was as high as 0.458 kWh/m3. Energy consumption increases with the increase in influent volume and COD reduction. The total energy consumption decreases with the NH3-N reduction. The water quality and energy consumption of wastewater treatment plants (WWTPs) in Taihu Basin were evaluated on the basis of the operation data from 204 municipal WWTPs in the basin by using various statistical methods. The influent ammonia nitrogen (NH3-N) and total nitrogen (TN) of WWTPs in Taihu Basin showed normal distribution, whereas chemical oxygen demand (COD), biochemical oxygen demand (BOD5), suspended solid (SS), and total phosphorus (TP) showed positively skewed distribution. The influent BOD5/COD was 0.4%–0.6%, only 39.2% SS/BOD5 exceeded the standard by 36.3%, the average BOD5/TN was 3.82, and the probability of influent BOD5/TP>20 was 82.8%. The average energy consumption of WWTPs in Taihu Basin in 2017 was 0.458 kWh/m3. The specific energy consumption of WWTPs with a daily treatment capacity of more than 5 × 104 m3 in Taihu Basin was stable at 0.33 kWh/m3. A power function relationship was observed between the reduction in COD and NH3-N and the specific energy consumption of pollutant reduction, and the higher the pollutant reduction is, the lower the specific energy consumption of pollutant reduction presents. In addition, a linear relationship existed between the energy consumption of WWTPs and the specific energy consumption of influent volume and pollutant reduction. Therefore, upgrading and operation with less energy consumption of WWTPs is imperative and the suggestions for Taihu WWTPs based on stringent discharge standard are proposed in detail.

关键词： Taihu Basin Wastewater treatment plant Influent characteristics Energy consumption evaluation Specific energy consumption SPSS correlation analysis

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Lung function and air pollution exposure in adults with asthma in Beijing: a 2-year longitudinal panel

《医学前沿（英文）》 2022年第16卷第4期页码 574-583 doi: 10.1007/s11684-021-0882-1

摘要： The effect of air pollution on the lung function of adults with asthma remains unclear to date. This study followed 112 patients with asthma at 3-month intervals for 2 years. The pollutant exposure of the participants was estimated using the inverse distance weight method. The participants were divided into three groups according to their lung function level at every visit. A linear mixed-effect model was applied to predict the change in lung function with each unit change in pollution concentration. Exposure to carbon monoxide (CO) and particles less than 2.5 micrometers in diameter (PM_2.5) was negatively associated with large airway function in participants. In the severe group, exposure to chronic sulfur dioxide (SO₂) was negatively associated with post-bronchodilator forced expiratory flow at 50%, between 25% and 75% of vital capacity % predicted (change of 95% CI per unit: −0.34 (−0.55, −0.12), −0.24 (−0.44, −0.03), respectively). In the mild group, the effect of SO₂ on the small airways was similar to that in the severe group, and it was negatively associated with large airway function. Exposure to CO and PM_2.5 was negatively associated with the large airway function of adults with asthma. The negative effects of SO₂ were more evident and widely observed in adults with severe and mild asthma than in adults with moderate asthma. Patients with asthma react differently to air pollutants as evidenced by their lung function levels.

关键词： lung function asthma air pollution adult

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The function and regulation of OTU deubiquitinases

Jiansen Du, Lin Fu, Yingli Sui, Lingqiang Zhang

《医学前沿（英文）》 2020年第14卷第5期页码 542-563 doi: 10.1007/s11684-019-0734-4

摘要： Post-translational modification of cellular proteins by ubiquitin regulates numerous cellular processes, including cell division, immune responses, and apoptosis. Ubiquitin-mediated control over these processes can be reversed by deubiquitinases (DUBs), which remove ubiquitin from target proteins and depolymerize polyubiquitin chains. Recently, much progress has been made in the DUBs. In humans, the ovarian tumor protease (OTU) subfamily of DUBs includes 16 members, most of which mediate cell signaling cascades. These OTUs show great variation in structure and function, which display a series of mechanistic features. In this review, we provide a comprehensive analysis of current progress in character, structure and function of OTUs, such as the substrate specificity and catalytic activity regulation. Then we discuss the relationship between some diseases and OTUs. Finally, we summarize the structure of viral OTUs and their function in immune escape and viral survival. Despite the challenges, OTUs might provide new therapeutic targets, due to their involvement in key regulatory processes.

关键词： ubiquitin OTU deubiquitinases structure function regulation