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Face recognition based on subset selection via metric learning on manifold

Hong SHAO,Shuang CHEN,Jie-yi ZHAO,Wen-cheng CUI,Tian-shu YU

《信息与电子工程前沿（英文）》 2015年第16卷第12期页码 1046-1058 doi: 10.1631/FITEE.1500085

摘要： With the development of face recognition using sparse representation based classification (SRC), many relevant methods have been proposed and investigated. However, when the dictionary is large and the representation is sparse, only a small proportion of the elements contributes to the 1-minimization. Under this observation, several approaches have been developed to carry out an efficient element selection procedure before SRC. In this paper, we employ a metric learning approach which helps find the active elements correctly by taking into account the interclass/intraclass relationship and manifold structure of face images. After the metric has been learned, a neighborhood graph is constructed in the projected space. A fast marching algorithm is used to rapidly select the subset from the graph, and SRC is implemented for classification. Experimental results show that our method achieves promising performance and significant efficiency enhancement.

关键词： Face recognition Sparse representation Manifold structure Metric learning Subset selection

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Xiao-hu MA,Meng YANG,Zhao ZHANG

《信息与电子工程前沿（英文）》 2016年第17卷第3期页码 212-223 doi: 10.1631/FITEE.1500255

摘要： The feature extraction algorithm plays an important role in face recognition. However, the extracted features also have overlapping discriminant information. A property of the statistical uncorrelated criterion is that it eliminates the redundancy among the extracted discriminant features, while many algorithms generally ignore this property. In this paper, we introduce a novel feature extraction method called local uncorrelated local discriminant embedding (LULDE). The proposed approach can be seen as an extension of a local discriminant embedding (LDE) framework in three ways. First, a new local statistical uncorrelated criterion is proposed, which effectively captures the local information of interclass and intraclass. Second, we reconstruct the affinity matrices of an intrinsic graph and a penalty graph, which are mentioned in LDE to enhance the discriminant property. Finally, it overcomes the small-sample-size problem without using principal component analysis to preprocess the original data, which avoids losing some discriminant information. Experimental results on Yale, ORL, Extended Yale B, and FERET databases demonstrate that LULDE outperforms LDE and other representative uncorrelated feature extraction methods.

关键词： Feature extraction Local discriminant embedding Local uncorrelated criterion Face recognition

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利用两类投影方法进行特征融合的人脸识别

张生亮,徐勇,杨健,杨静宇

《中国工程科学》 2006年第8卷第8期页码 50-55

摘要：

提出了利用两类投影抽取特征、用并行策略融合特征进行人脸识别的新方法。先用一维的基于向量的投影抽取一组特征，再用基于二维的图像投影的方法抽取一组特征，用复向量将样本的两组特征向量组合在一起，在复向量空间分析主分量(CPCA)，抽取人脸图像的鉴别特征。在FERET人脸库上的实验结果表明，该方法的识别性能比用单个特征有10%左右的提高。

关键词：特征融合线性鉴别分析(LDA) 特征抽取人脸识别

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统计不相关最佳鉴别矢量集的本质研究

吴小俊,杨静宇,王士同,刘同明,Josef Kittler

《中国工程科学》 2004年第6卷第2期页码 44-47

摘要：

对统计不相关最佳鉴别矢量集的本质进行研究，在基于总体散布矩阵特征分解的基础上，构造了一种白化变换，使得变换后的样本空间中的总体散布矩阵为单位矩阵，这样使得传统的最佳鉴别矢量集算法得到的均是具有统计不相关的最佳鉴别矢量集，从而揭示了统计不相关最佳鉴别变换的本质——白化变换加普通的线性鉴别变换。该方法的最大优点在于所获得的最优鉴别矢量同时具有正交性和统计不相关性。该方法对代数特征抽取具有普遍适用性。用ORL人脸数据库的数值实验，验证了该方法的有效性。

关键词：模式识别特征抽取鉴别分析广义最佳鉴别矢量集人脸识别

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Effect of cutterhead configuration on tunnel face stability during shield machine maintenance outages

《结构与土木工程前沿（英文）》 2023年第17卷第4期页码 522-532 doi: 10.1007/s11709-023-0930-9

摘要： Owing to long-distance advancement or obstacles, shield tunneling machines are typically shut down for maintenance. Engineering safety during maintenance outages is determined by the stability of the tunnel face. Pressure maintenance openings are typically used under complicated hydrogeological conditions. The tunnel face is supported by a medium at the bottom of the excavation chamber and compressed air at the top. Owing to the high risk of face failure, the necessity of support pressure when cutterhead support is implemented and a method for determining the value of compressed air pressure using different support ratios must to be determined. In this study, a non-fully chamber supported rotational failure model considering cutterhead support is developed based on the upper-bound theorem of limit analysis. Numerical simulation is conducted to verify the accuracy of the proposed model. The results indicate that appropriately increasing the specific gravity of the supporting medium can reduce the risk of collapse. The required compressed air pressure increases significantly as the support ratio decreases. Disregarding the supporting effect of the cutterhead will result in a tunnel face with underestimated stability. To satisfy the requirement of chamber openings at atmospheric pressure, the stratum reinforcement strength and range at the shield end are provided based on different cutterhead aperture ratios.

关键词： tunnel face stability cutterhead configuration aperture ratio pressure gradient support ratio

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Method for solving the nonlinear inverse problem in gas face seal diagnosis based on surrogate models

《机械工程前沿（英文）》 2022年第17卷第3期 doi: 10.1007/s11465-022-0689-z

摘要： Physical models carry quantitative and explainable expert knowledge. However, they have not been introduced into gas face seal diagnosis tasks because of the unacceptable computational cost of inferring the input fault parameters for the observed output or solving the inverse problem of the physical model. The presented work develops a surrogate-model-assisted method for solving the nonlinear inverse problem in limited physical model evaluations. The method prepares a small initial database on sites generated with a Latin hypercube design and then performs an iterative routine that benefits from the rapidity of the surrogate models and the reliability of the physical model. The method is validated on simulated and experimental cases. Results demonstrate that the method can effectively identify the parameters that induce the abnormal signal output with limited physical model evaluations. The presented work provides a quantitative, explainable, and feasible approach for identifying the cause of gas face seal contact. It is also applicable to mechanical devices that face similar difficulties.

关键词： surrogate model gas face seal fault diagnosis nonlinear dynamics tribology

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Strengthening of the concrete face slabs of dams using sprayable strain-hardening fiber-reinforced cementitious

《结构与土木工程前沿（英文）》 2022年第16卷第2期页码 145-160 doi: 10.1007/s11709-022-0806-4

摘要： In this study, sprayable strain-hardening fiber-reinforced cementitious composites (FRCC) were applied to strengthen the concrete slabs in a concrete-face rockfill dam (CFRD) for the first time. Experimental, numerical, and analytical investigations were carried out to understand the flexural properties of FRCC-layered concrete slabs. It was found that the FRCC layer improved the flexural performance of concrete slabs significantly. The cracking and ultimate loads of a concrete slab with an 80 mm FRCC layer were 132% and 69% higher than those of the unstrengthened concrete slab, respectively. At the maximum crack width of 0.2 mm, the deflection of the 80-mm FRCC strengthened concrete slab was 144% higher than that of the unstrengthened concrete slab. In addition, a FE model and a simplified analytical method were developed for the design and analysis of FRCC-layered concrete slabs. Finally, the test result of FRCC leaching solution indicated that the quality of the water surrounding FRCC satisfied the standard for drinking water. The findings of this study indicate that the sprayable strain-hardening FRCC has a good potential for strengthening hydraulic structures such as CFRDs.

关键词： strain-hardening cementitious composites engineered cementitious composites sprayable shotcrete strengthening concrete-face rockfill dam digital image correlation

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Dynamic in-plane transversal normal stresses in the concrete face of CFRD

Neftalí SARMIENTO-SOLANO, Miguel P. ROMO

《结构与土木工程前沿（英文）》 2019年第13卷第1期页码 135-148 doi: 10.1007/s11709-018-0481-7

摘要： Severe earthquakes can induce damages to Concrete Face Rockfill Dams (CFRDs) such as concrete cracking and joint's water stops distressing where high in-plane transversal normal stresses develop. Although these damages rarely jeopardize the dam safety, they cause large water reservoir leakages that hinder the dam functioning. This issue can be addressed using well know numerical methods; however, given the wide range of parameters involved, it would seem appropriate to develop a simple yet reliable procedure to get a close understanding how their interaction affects the CFRD’s overall behavior. Accordingly, once the physics of the problem is better understood one can proceed to perform a detailed design of the various components of the dam. To this end an easy-to-use procedure that accounts for the dam height effects, valley narrowness, valley slopes, width of concrete slabs and seismic excitation characteristics was developed. The procedure is the dynamic complement of a method recently developed to evaluate in-plane transversal normal stresses in the concrete face of CFRD’s due to dam reservoir filling [ ]. Using these two procedures in a sequential manner, it is possible to define the concrete slab in-plane normal stresses induced by the reservoir filling and the action of orthogonal horizontal seismic excitations acting at the same time upstream-downstream and cross river. Both procedures were developed from a data base generated using nonlinear static and dynamic three-dimensional numerical analyses on the same group of CFRD’s. Then, the results were interpreted with the Buckingham Pi theorem and various relationships were developed. In the above reference, the method to evaluate the concrete face in-plane transversal normal stresses caused by the first reservoir filling was reported. In this paper, the seismic procedure is first developed and then through an example the whole method (dam construction, reservoir filling plus seismic loading) of analysis is assessed.

关键词： CFR dams dynamic analysis in-plane normal stresses concrete face

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Multiobjective image recognition algorithm in the fully automatic die bonder

JIANG Kai, CHEN Hai-xia, YUAN Sen-miao

《机械工程前沿（英文）》 2006年第1卷第3期页码 313-316 doi: 10.1007/s11465-006-0026-y

摘要： It is a very important task to automatically fix the number of die in the image recognition system of a fully automatic die bonder. A multiobjective image recognition algorithm based on clustering Genetic Algorithm (GA), is proposed in this paper. In the evolutionary process of GA, a clustering method is provided that utilizes information from the template and the fitness landscape of the current population. The whole population is grouped into different niches by the clustering method. Experimental results demonstrated that the number of target images could be determined by the algorithm automatically, and multiple targets could be recognized at a time. As a result, time consumed by one image recognition is shortened, the performance of the image recognition system is improved, and the atomization of the system is fulfilled.

关键词： clustering different recognition algorithm Algorithm multiobjective

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In-plane transversal normal stresses in the concrete face of CFRD induced by the first-dam reservoir

Neftalí SARMIENTO-SOLANO, Miguel P. ROMO

《结构与土木工程前沿（英文）》 2018年第12卷第1期页码 81-91 doi: 10.1007/s11709-016-0378-2

摘要： To evaluate the effects of dam height, valley narrowness and width of concrete slabs on the first-dam reservoir filling in-plane transversal normal stresses in the concrete face of CFRD´s, 3D finite difference analyses were carried out. Behavior of rockfill dams considered in this study was defined from the monitoring of a number of 3D sets of pressure cells and extensometers installed in three large dams in Mexico. The 3D analyses results show that high in-plane transversal compressive stresses develop within the concrete panels located in the central concrete face zone upon dam reservoir filling loading. Likewise, in-plane induced tensile transversal stresses in the zones near the abutments increase the potential of slabs cracking and damaging the waterstops in-between the vertical and perimetral joints. From the results of the 3D finite difference analyses, a simple method to estimate in-plane normal stresses in the concrete face is advanced and through comparisons with the results of a 3D case numerical study, its accuracy assessed.

关键词： concrete face CFR dams reservoir filling slab in-plane stresses

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激活–效价维度空间中基于脸部图像的情感等级排序方法 None

Guo-peng XU, Hai-tang LU, Fei-fei ZHANG, Qi-rong MAO

《信息与电子工程前沿（英文）》 2018年第19卷第6期页码 783-795 doi: 10.1631/FITEE.1700270

摘要：在维度情感识别领域，分类和回归通常被用来对情感的机器学习进行建模和预测。然而，在维度情感空间中，情感标注通常是一个连续的实数值，拥有有序属性。而前面所提的两种方法并没有考虑并利用这一重要信息。因此，我们提出一个在激活和效价维度空间下的基于脸部图像的情感等级排序框架。我们的方法能够通过离散化连续的情感标注得到情感等级，并恰当地利用它们之间的有序信息。确切地说，首先训练一系列基本误差敏感二分类器，每个二分类器都使用经过二值重新标注的全部样本。依据样本对应的情感等级与给定二分类器对应的情感等级的比较结果，对二值进行重新标注。然后通过聚合所有二分类器的输出结果，可以得到样本最终的情感等级预测结果。在AVEC 2015挑战赛标准数据集和SEMAINE子集数据集上对所提方法与基本的和基于深度学习的分类和回归方法进行比较。实验结果表明，所提出的基于排序的情感识别方法在激活和效价两个维度上都是有效的。

关键词：有序排序；维度情感识别；效价度；激活度；脸部图像处理

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Advances in tissue state recognition in spinal surgery: a review

Hao Qu, Yu Zhao

《医学前沿（英文）》 2021年第15卷第4期页码 575-584 doi: 10.1007/s11684-020-0816-3

摘要： Spinal disease is an important cause of cervical discomfort, low back pain, radiating pain in the limbs, and neurogenic intermittent claudication, and its incidence is increasing annually. From the etiological viewpoint, these symptoms are directly caused by the compression of the spinal cord, nerve roots, and blood vessels and are most effectively treated with surgery. Spinal surgeries are primarily performed using two different techniques: spinal canal decompression and internal fixation. In the past, tactile sensation was the primary method used by surgeons to understand the state of the tissue within the operating area. However, this method has several disadvantages because of its subjectivity. Therefore, it has become the focus of spinal surgery research so as to strengthen the objectivity of tissue state recognition, improve the accuracy of safe area location, and avoid surgical injury to tissues. Aside from traditional imaging methods, surgical sensing techniques based on force, bioelectrical impedance, and other methods have been gradually developed and tested in the clinical setting. This article reviews the progress of different tissue state recognition methods in spinal surgery and summarizes their advantages and disadvantages.

关键词： spinal surgery tissue state recognition image force sensing bioelectrical impedance

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Model test and discrete element method simulation of shield tunneling face stability in transparent clay

Huayang LEI, Yajie ZHANG, Yao HU, Yingnan LIU

《结构与土木工程前沿（英文）》 2021年第15卷第1期页码 147-166 doi: 10.1007/s11709-020-0704-6

摘要： The stability of the shield tunneling face is an extremely important factor affecting the safety of tunnel construction. In this study, a transparent clay with properties similar to those of Tianjin clay is prepared and a new transparent clay model test apparatus is developed to overcome the “black box” problem in the traditional model test. The stability of the shield tunneling face (failure mode, influence range, support force, and surface settlement) is investigated in transparent clay under active failure. A series of transparent clay model tests is performed to investigate the active failure mode, influence range, and support force of the shield tunneling face under different burial depth conditions, whereas particle flow code three-dimensional numerical simulations are conducted to verify the failure mode of the shield tunneling face and surface settlement along the transverse section under different burial depth conditions. The results show that the engineering characteristics of transparent clay are similar to those of soft clay in Binhai, Tianjin and satisfy visibility requirements. Two types of failure modes are obtained: the overall failure mode (cover/diameter: / ≤1.0) and local failure mode ( / ≥2.0). The influence range of the transverse section is wider than that of the longitudinal section when / ≥2.0. Additionally, the normalized thresholds of the relative displacement and support force ratio are 3%–6% and 0.2–0.4, respectively. Owing to the cushioning effect of the clay layer, the surface settlement is significantly reduced as the tunnel burial depth increases.

关键词： shield tunneling face stability transparent clay model test numerical simulation

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Investigation of Generalized SIFs of cracks in 3D piezoelectric media under various crack-face conditions

Jaroon RUNGAMORNRAT, Bounsana CHANSAVANG, Weeraporn PHONGTINNABOOT, Chung Nguyen VAN

《结构与土木工程前沿（英文）》 2020年第14卷第2期页码 280-298 doi: 10.1007/s11709-019-0586-7

摘要： This paper investigates the influence of crack geometry, crack-face and loading conditions, and the permittivity of a medium inside the crack gap on intensity factors of planar and non-planar cracks in linear piezoelectric media. A weakly singular boundary integral equation method together with the near-front approximation is adopted to accurately determine the intensity factors. Obtained results indicate that the non-flat crack surface, the electric field, and the permittivity of a medium inside the crack gap play a crucial role on the behavior of intensity factors. The mode-I stress intensity factors ( ) for two representative non-planar cracks under different crack-face conditions are found significantly different and they possess both upper and lower bounds. In addition, for impermeable and semi-permeable non-planar cracks treated depends strongly on the electric field whereas those of impermeable, permeable, and semi-permeable penny-shaped cracks are identical and independent of the electric field. The stress/electric intensity factors predicted by permeable and energetically consistent models are, respectively, independent of and dependent on the electric field for the penny-shaped crack and the two representative non-planar cracks. Also, the permittivity of a medium inside the crack gap strongly affects the intensity factors for all crack configurations considered except for of the semi-permeable penny-shaped crack.

关键词： crack-face conditions intensity factors non-flat cracks permittivity piezoelectric media SGBEM

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气球机器人在室内环境下与人的自然交互 None

Ning-shi YAO, Qiu-yang TAO, Wei-yu LIU, Zhen LIU, Ye TIAN, Pei-yu WANG, Timothy LI, Fumin ZHANG

《信息与电子工程前沿（英文）》 2019年第20卷第1期页码 45-59 doi: 10.1631/FITEE.1800587

摘要：为支持室内环境下长达两小时及以上的人机交互实验，我们研发了一款“佐治亚理工全自动迷你气球飞行机器人”（GT-MAB）。GT-MAB可以安全地与人近距离互动。该机器人具有人脸识别、自动跟踪人类使用者以及手势识别等功能。采用深度人工神经网络检测GT-MAB实时视频信号中人类使用者的脸和手，并基于此功能，设计一套人机交互系统实现GT-MAB与使用者之间的自然交互。GT-MAB的学习算法可以自主识别两种手势，因此在交互过程中，使用者无需佩戴任何装置就可与GT-MAB互动。基于机器视觉的反馈控制器可控制GT-MAB自动追踪并跟随使用者。一旦机器人成功识别使用者的手势，机器人会以对应的飞行轨迹回应使用者手势，同时将识别结果以及意图通过其自身搭载的LED显示屏展示给使用者。实验数据表明，向人类使用者展示的视觉信号能明显提高人类使用者和GT-MAB之间的交互体验。实验结果表明，GT-MAB作为一款新型飞行机器人，可在室内环境下安全地与人互动并有效采集人机交互数据。

关键词：气球机器人；人机交互；深度学习；人脸识别；手势识别

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标题作者时间类型操作

Face recognition based on subset selection via metric learning on manifold

Hong SHAO,Shuang CHEN,Jie-yi ZHAO,Wen-cheng CUI,Tian-shu YU

期刊论文

Local uncorrelated local discriminant embedding for face recognition

Xiao-hu MA,Meng YANG,Zhao ZHANG

期刊论文

利用两类投影方法进行特征融合的人脸识别

张生亮,徐勇,杨健,杨静宇

期刊论文