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关键词

中子通量密度 2

功率密度 2

功率谱密度 2

参数估计 2

2R-1C模型；嵌入式系统；参数估计；非迭代方法；二次型 1

8英寸 1

Arrhenius模型 1

Au/Ti双功能催化剂 1

BNCT医院中子照射器 1

CP）；符号间干扰（inter symbol interference， ISI）；载波间干扰（inter carrier interference 1

GPU；密度峰值；聚类；并行计算 1

H₂有效利用率 1

ICI）；最大似然估计（maximum likelihood estimation 1

IKPCA 1

KPCA 1

LS算法 1

MLE） 1

OFDM 1

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Seismic fragility curves for structures using non-parametric representations

Chu MAI, Katerina KONAKLI, Bruno SUDRET

《结构与土木工程前沿（英文）》 2017年第11卷第2期页码 169-186 doi: 10.1007/s11709-017-0385-y

摘要： Fragility curves are commonly used in civil engineering to assess the vulnerability of structures to earthquakes. The probability of failure associated with a prescribed criterion (e.g., the maximal inter-storey drift of a building exceeding a certain threshold) is represented as a function of the intensity of the earthquake ground motion (e.g., peak ground acceleration or spectral acceleration). The classical approach relies on assuming a lognormal shape of the fragility curves; it is thus parametric. In this paper, we introduce two non-parametric approaches to establish the fragility curves without employing the above assumption, namely binned Monte Carlo simulation and kernel density estimation. As an illustration, we compute the fragility curves for a three-storey steel frame using a large number of synthetic ground motions. The curves obtained with the non-parametric approaches are compared with respective curves based on the lognormal assumption. A similar comparison is presented for a case when a limited number of recorded ground motions is available. It is found that the accuracy of the lognormal curves depends on the ground motion intensity measure, the failure criterion and most importantly, on the employed method for estimating the parameters of the lognormal shape.

关键词： earthquake engineering fragility curves lognormal assumption non-parametric approach kernel density estimation epistemic uncertainty

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An assessment of surrogate fuel using Bayesian multiple kernel learning model in sight of sooting tendency

《能源前沿（英文）》 2022年第16卷第2期页码 277-291 doi: 10.1007/s11708-021-0731-6

摘要： An integrated and systematic database of sooting tendency with more than 190 kinds of fuels was obtained through a series of experimental investigations. The laser-induced incandescence (LII) method was used to acquire the 2D distribution of soot volume fraction, and an apparatus-independent yield sooting index (YSI) was experimentally obtained. Based on the database, a novel predicting model of YSI values for surrogate fuels was proposed with the application of a machine learning method, named the Bayesian multiple kernel learning (BMKL) model. A high correlation coefficient (0.986) between measured YSIs and predicted values with the BMKL model was obtained, indicating that the BMKL model had a reliable and accurate predictive capacity for YSI values of surrogate fuels. The BMKL model provides an accurate and low-cost approach to assess surrogate performances of diesel, jet fuel, and biodiesel in terms of sooting tendency. Particularly, this model is one of the first attempts to predict the sooting tendencies of surrogate fuels that concurrently contain hydrocarbon and oxygenated components and shows a satisfying matching level. During surrogate formulation, the BMKL model can be used to shrink the surrogate candidate list in terms of sooting tendency and ensure the optimal surrogate has a satisfying matching level of soot behaviors. Due to the high accuracy and resolution of YSI prediction, the BMKL model is also capable of providing distinguishing information of sooting tendency for surrogate design.

关键词： sooting tendency yield sooting index Bayesian multiple kernel learning surrogate assessment surrogate formulation

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Fast implementation of kernel simplex volume analysis based on modified Cholesky factorization for endmember

Jing LI,Xiao-run LI,Li-jiao WANG,Liao-ying ZHAO

《信息与电子工程前沿（英文）》 2016年第17卷第3期页码 250-257 doi: 10.1631/FITEE.1500244

摘要： Endmember extraction is a key step in the hyperspectral image analysis process. The kernel new simplex growing algorithm (KNSGA), recently developed as a nonlinear alternative to the simplex growing algorithm (SGA), has proven a promising endmember extraction technique. However, KNSGA still suffers from two issues limiting its application. First, its random initialization leads to inconsistency in final results; second, excessive computation is caused by the iterations of a simplex volume calculation. To solve the first issue, the spatial pixel purity index (SPPI) method is used in this study to extract the first endmember, eliminating the initialization dependence. A novel approach tackles the second issue by initially using a modified Cholesky factorization to decompose the volume matrix into triangular matrices, in order to avoid directly computing the determinant tautologically in the simplex volume formula. Theoretical analysis and experiments on both simulated and real spectral data demonstrate that the proposed algorithm significantly reduces computational complexity, and runs faster than the original algorithm.

关键词： Endmember extraction Modified Cholesky factorization Spatial pixel purity index (SPPI) New simplex growing algorithm (NSGA) Kernel new simplex growing algorithm (KNSGA)

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Development of soft kernel durum wheat

Craig F. MORRIS

《农业科学与工程前沿（英文）》 2019年第6卷第3期页码 273-278 doi: 10.15302/J-FASE-2019259

摘要：

Kernel texture (grain hardness) is a fundamental and determining factor related to wheat ( spp.) milling, baking and flour utilization. There are three kernel texture classes in wheat: soft and hard hexaploid ( ), and very hard durum ( subsp. ). The genetic basis for these three classes lies with the Puroindoline genes. Phenotypically, the easiest means of quantifying kernel texture is with the Single Kernel Characterization System (SKCS), although other means are valid and can provide fundamental material properties. Typical SKCS values for soft wheat would be around 25 and for durum wheat≥80. Soft kernel durum wheat was created via homeologous recombination using the mutation, which facilitated the transfer of ca. 28 Mbp of 5DS that replaced ca. 21 Mbp of 5BS. The 5DS translocation contained a complete and intact locus and both puroindoline genes. Expression of the puroindoline genes in durum grain resulted in kernel texture and flour milling characteristics nearly identical to that of soft wheat, with high yields of break and straight-grade flours, which had small particle size and low starch damage. Dough water absorption was markedly reduced compared to durum flour and semolina. Dough was essentially unchanged and reflected the inherent gluten properties of the durum background. Pasta quality was essentially equal-to-or-better than pasta made from semolina. Agronomically, soft durum germplasm showed good potential with moderate grain yield and resistance to a number of fungal pathogens and insects. Future breeding efforts will no doubt further improve the quality and competitiveness of soft durum cultivars.

关键词： soft durum wheat grain hardness puroindolines milling baking pasta noodles

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Boundedness of Marcinkiewicz integralwith rough kernel onTriebel-Lizorkin spaces

Chun-jie ZHANG,Fang-fang REN,Yu-huai ZHANG,Gui-lian GAO

《信息与电子工程前沿（英文）》 2015年第16卷第8期页码 654-657 doi: 10.1631/FITEE.1500082

摘要： This paper is a continuation of our previous work (Zhang and Chen, 2010b). Following the same general steps of the proof there, we make essential improvement on our previous theorem by recalculating a key inequality. Our result shows that the Marcinkiewicz integral, with a bounded radial function in its kernel, is still bounded on the Triebel-Lizorkin space.

关键词： Marcinkiewicz integral Triebel-Lizorkin spaces

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基于核空间非线性特征提取的图像质量评价方法 Article

Yong DING,Nan LI,Yang ZHAO,Kai HUANG

《信息与电子工程前沿（英文）》 2016年第17卷第10期页码 1008-1017 doi: 10.1631/FITEE.1500439

摘要：不同于传统方法中通过线性变换或模型表达图像的方式，本文采用高维空间的一种数学表达来揭示图像的统计特性，通过引入核独立分量分析（kernel independent component analysis,

关键词：图像质量评价；全参考方法；特征提取；核空间；支持向量回归

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基于核空间投影和联合表征的跳频信号辐射源指纹特征识别 Research Articles

Ping SUI, Ying GUO, Kun-feng ZHANG, Hong-guang LI

《信息与电子工程前沿（英文）》 2019年第20卷第8期页码 1133-1146 doi: 10.1631/FITEE.1800025

摘要：跳频作为扩频通信的一种常用技术，以其截获概率低、抗干扰能力强和保密性好等优点，在雷达和通信系统中得到广泛应用。然而，非合作条件下的跳频信号辐射源识别作为一大难题，不仅由于其对噪声影响敏感，信号的非线性、非高斯性和非平稳性使得很难在其原始信号空间实现跳频信号分类识别。现有的一些分类识别算法，如稀疏表征分类算法（SRC），仅使用单个信号样本而非整体样本表征测试数据，过分强调稀疏特性而忽略信号样本之间的相关性。为解决上述问题，本文提出一种基于核空间投影和联合表征的跳频信号辐射源指纹特征识别方法。该方法将核空间投影、相关特性表征以及个体分类学习融合到同一个联合表征框架，通过该框架实现辐射源信号分类识别。实际跳频信号的大量实验表明，与几种最先进的识别方法相比，所提算法具有可行性和有效性。

关键词：跳频信号；指纹特征；核函数；联合表征；辐射源识别

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基于核稀疏表示的磁共振图像分析及其在脑肿瘤自动分割中的应用 None

Ji-jun TONG, Peng ZHANG, Yu-xiang WENG, Dan-hua ZHU

《信息与电子工程前沿（英文）》 2018年第19卷第4期页码 471-480 doi: 10.1631/FITEE.1620342

摘要：脑肿瘤分割在疾病辅助诊断、治疗方案规划以及手术导航中扮演重要角色。对脑肿瘤精确分割可以帮助临床医生获取肿瘤位置、尺寸和形状信息。提出一种基于核稀疏编码的全自动脑肿瘤分割方法，并在3D多模态磁共振成像图（magnetic resonance imaging, MRI）上验证。首先对MRI图像进行预处理以减少噪声，然后通过核字典学习提取非线性特征，用来构建坏死组织、水肿组织、非增强肿瘤组织、增强肿瘤组织和健康组织5个适应性字典。对从原始MRI图像上肿瘤像素点周边m×m×m的小区域提取的特征向量进行稀疏编码，并通过一种基于字典学习的核聚类方法对像素点进行编码。最后通过形态滤波填充在多个相连部分间的区域，提高分割质量。为评估分割表现，分割结果被上传到在线评估系统中，该评估系统使用dice系数、阳性预测值（positive predictive value, PPV）、灵敏度和kappa值作为评估指标。结果表明，该方法在完整肿瘤区域分割上具有良好表现（dice: 0.83; PPV: 0.84; sensitivity: 0.82），而在肿瘤核心区域（dice: 0.69; PPV: 0.76; sensitivity: 0.80）和增强肿瘤区域（dice: 0.58; PPV: 0.60; sensitivity: 0.65）上表现稍差。相较于脑肿瘤分割（BRATS）挑战中其他团队采用的方法，该方法具有竞争力。该方法在健康组织和病理组织区分上具有一定潜力。

关键词：脑肿瘤分割；核方法；稀疏编码；字典学习

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一种新的基于卷积神经网络的人群计数方法 Research Articles

黄杰浩,遆晓光,吴俊德,陈瑷玥

《信息与电子工程前沿（英文）》 2020年第21卷第8期页码 1119-1266 doi: 10.1631/FITEE.1900282

摘要：人群密度估计是一项具有挑战性的任务，因为人群中人头大小存在大范围变化。现有方法均采用多列式结构卷积神经网络去适应这种变化，但会导致密度图上不同密度区域产生平均效应并引入额外噪声。为解决该问题，提出一种新的基于分割先验图的神经网络方法，在分割图基础上生成一个高质量且没有噪声的密度图。该网络主要包括两个部分，即头部的人群前景分割神经网络和尾部的人群回归神经网络。在数据集只提供单点人头标记的情况下，采用均匀函数生成人群头部的掩膜真值图。基于该真值图，前景分割网络输出人群分割图，可有效减少密度图中无人区域噪声。将人群分割图输入人群回归网络，后者能生成高质量人群密度图并提供准确的人数估计。在4个公开数据集（即ShanghaiTech、UCF-CC-50、WorldExpo’10和UCSD）上验证了所提方法有效性；其中，在ShanghaiTech part B和UCF-CC-50两个数据集上该方法取得了当前最好结果。

关键词：人群计数；密度估计；分割先验图；均匀函数

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Effect of current density on groundwater arsenite removal performance using air cathode electrocoagulation

《环境科学与工程前沿（英文）》 2021年第15卷第6期 doi: 10.1007/s11783-021-1399-1

摘要：

• With the same charge, current density had little effect on As(III) removal in ACEC.

关键词： Electrocoagulation Air cathode Arsenic Current density Energy consumption

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Effects of exercise therapy on bone mineral density in early postmenopausal women: a controlled trial

Shilin DENG MD ,

《医学前沿（英文）》 2009年第3卷第3期页码 323-329 doi: 10.1007/s11684-009-0061-2

摘要： The purpose of this article is to determine the effect of a well-designed combined aerobic, resistance, and extension exercise program on bone mineral density (BMD) in postmenopausal women. The population comprised 45 postmenopausal women, who exercised over 12months (exercise group), and 36 women who served as a non-training control group. BMD of the hip, and lumbar spine was measured at the baseline and 12th month. Repeated measurement analysis of variance and nonparametric test were utilized to compare differences between the exercise group and controls. Thirty-six out of 45 persons in the exercise group and 36 controls completed the study. Average compliance was 82.2% for the whole exercise group at the 12th month. All the subjects had decreased BMD, but the rate of bone loss was lower in the exercise group than in the control group at the L4 and hip. Although the exercise program in this study may probably reduce the rate of bone loss in weight-bearing skeletal sites, we do not suggest the exercise by itself be viewed as prevention or treatment for osteoporosis. Further, the exact dose-response relationship of exercise and bone mass in early postmenopause is not clear.

关键词： early postmenopausal women bone mineral density exercise effects

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density measurement for plastic injection molding via ultrasonic technology

《机械工程前沿（英文）》 2022年第17卷第4期 doi: 10.1007/s11465-022-0714-2

摘要： Density variation during the injection molding process directly reflects the state of plastic melt and contains valuable information for process monitoring and optimization. Therefore, in-situ density measurement is of great interest and has significant application value. The existing methods, such as pressure−volume−temperature (PVT) method, have the shortages of time-delay and high cost of sensors. This study is the first to propose an in-situ density measurement method using ultrasonic technology. The analyses of the time-domain and frequency-domain signals are combined in the proposed method. The ultrasonic velocity is obtained from the time-domain signals, and the acoustic impedance is computed through a full-spectral analysis of the frequency-domain signals. Experiments with different process conditions are conducted, including different melt temperature, injection speed, material, and mold structure. Results show that the proposed method has good agreement with the PVT method. The proposed method has the advantages of in-situ measurement, non-destructive, high accuracy, low cost, and is of great application value for the injection molding industry.

关键词： ultrasonic measurement melt density in-situ measurement injection molding

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Intelligent algorithm for optimal meter placement and bus voltage estimation in ring main distribution

L. RAMESH, N. CHAKRABORTY, S. P. CHOWDHURY

《能源前沿（英文）》 2012年第6卷第1期页码 47-56 doi: 10.1007/s11708-011-0159-5

摘要： The advancement in power distribution system poses a great challenge to power engineering researchers on how to best monitor and estimate the state of the distribution network. This paper is executed in two stage processes. The first stage is to identify the optimal location for installation of monitoring instrument with minimal investment cost. The second stage is to estimate the bus voltage magnitude, where real time measurement is conducted and measured through identified meter location which is more essential for decision making in distribution supervisory control and data acquisition system (DSCADA). The hybrid intelligent technique is applied to execute the above two algorithms. The algorithms are tested with institute of electrical and electronics engineers (IEEE) and Tamil Nadu electricity board (TNEB) benchmark systems. The simulated results proves that the swarm tuned artificial neural network (ANN) estimator is best suited for accurate estimation of voltage with different noise levels.

关键词： artificial intelligence power distribution control state estimation

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An operating state estimation model for integrated energy systems based on distributed solution

Dengji ZHOU, Shixi MA, Dawen HUANG, Huisheng ZHANG, Shilie WENG

《能源前沿（英文）》 2020年第14卷第4期页码 801-816 doi: 10.1007/s11708-020-0687-y

摘要： In view of the disadvantages of the traditional energy supply systems, such as separate planning, separate design, independent operating mode, and the increasingly prominent nonlinear coupling between various sub-systems, the production, transmission, storage and consumption of multiple energy sources are coordinated and optimized by the integrated energy system, which improves energy and infrastructure utilization, promotes renewable energy consumption, and ensures reliability of energy supply. In this paper, the mathematical model of the electricity-gas interconnected integrated energy system and its state estimation method are studied. First, considering the nonlinearity between measurement equations and state variables, a performance simulation model is proposed. Then, the state consistency equations and constraints of the coupling nodes for multiple energy sub-systems are established, and constraints are relaxed into the objective function to decouple the integrated energy system. Finally, a distributed state estimation framework is formed by combining the synchronous alternating direction multiplier method to achieve an efficient estimation of the state of the integrated energy system. A simulation model of an electricity-gas interconnected integrated energy system verifies the efficiency and accuracy of the state estimation method proposed in this paper. The results show that the average relative errors of voltage amplitude and node pressure estimated by the proposed distributed state estimation method are only 0.0132% and 0.0864%, much lower than the estimation error by using the Lagrangian relaxation method. Besides, compared with the centralized estimation method, the proposed distributed method saves 5.42 s of computation time. The proposed method is more accurate and efficient in energy allocation and utilization.

关键词： integrated energy system state estimation electricity-gas coupling energy system nonlinear coupling distributed solution

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Bayes estimation of residual life by fusing multisource information

Qian ZHAO, Xiang JIA, Zhi-jun CHENG, Bo GUO

《工程管理前沿（英文）》 2018年第5卷第4期页码 524-532 doi: 10.15302/J-FEM-2018034

摘要：

Residual life estimation is essential for reliability engineering. Traditional methods may experience difficulties in estimating the residual life of products with high reliability, long life, and small sample. The Bayes model provides a feasible solution and can be a useful tool for fusing multisource information. In this study, a Bayes model is proposed to estimate the residual life of products by fusing expert knowledge, degradation data, and lifetime data. The linear Wiener process is used to model degradation data, whereas lifetime data are described via the inverse Gaussian distribution. Therefore, the joint maximum likelihood (ML) function can be obtained by combining lifetime and degradation data. Expert knowledge is used according to the maximum entropy method to determine the prior distributions of parameters, thereby making this work different from existing studies that use non-informative prior. The discussion and analysis of different types of expert knowledge also distinguish our research from others. Expert knowledge can be classified into three categories according to practical engineering. Methods for determining prior distribution by using the aforementioned three types of data are presented. The Markov chain Monte Carlo is applied to obtain samples of the parameters and to estimate the residual life of products due to the complexity of the joint ML function and the posterior distribution of parameters. Finally, a numerical example is presented. The effectiveness and practicability of the proposed method are validated by comparing it with residual life estimation that uses non-informative prior. Then, its accuracy and correctness are proven via simulation experiments.

关键词： residual life estimation Bayes model linear Wiener process