Rule extraction for voltage security margin estimation

Research efforts have been devoted to estimating voltage security margins which show how close the current operating point of a power system is to a voltage collapse point as assessment of voltage security. One main disadvantage of these techniques is that they require large computations, therefore, they are not efficient for on-line use in power control centers. In this paper, we propose a technique based on hyperrectangular composite neural networks (HRCNNs) and fuzzy hyperrectangular composite neural networks (FHRCNNs) for voltage security margin estimation. The technique provides us with much faster assessments of voltage security than conventional techniques. The two classes of HRCNNs and FHRCNNs integrate the paradigm of neural networks with the rule-based approach, rendering them more useful than either. The values of the network parameters, after sufficient training, can be utilized to generate crisp or fuzzy rules on the basis of preselected meaningful features. Extracted rules are helpful to explain the whole assessment procedure so the assessments are more capable of being trusted. In addition, the power system operators or corresponding experts can delete unimportant features or add some additional features to improve the performance and computational efficiency based on the evaluation of the extracted rules. The proposed technique was tested on 3000 simulated data randomly generated from operating conditions on the IEEE 30-bus system to indicate its high efficiency     

Real-time Hand Gesture Recognition from Depth Images Using Convex Shape Decomposition Method

Hand gesture recognition is one of the most natural and intuitive ways to communicate between people and machines, since it closely mimics how human interact with each other. This paper presents a novel method for real-time markerless hand gesture recognition from depth images. The proposed method encompasses a collection of techniques that enable the detection, segmentation and recognition of hand gestures. A Hand detection and location method is employed using the depth information acquired from a depth sensor. Then, the hand is robustly segmented in cluttered background without any marker around. A convex shape decomposition method based on Radius Morse function is proposed for hand shape decomposition in real-time. Hand palm, fingertips and hand skeleton are recognized based on the hand shape decomposition and hand features. Moreover, we present a method for recognition of two-hand gestures. Representative experimental results demonstrate qualitatively and quantitatively that accurate hand gesture recognition can be achieved for real-time applications.     

复杂人机交互场景下的指势用户对象识别

采用指势进行人机交互,可充分发挥人类日常技能,摆脱常规输入设备束缚.实现自然的指势人机交互的关键是,如何从复杂的人机交互场景中有效提取指势用户对象,提出了基于时/空运动特征的指势用户对象识别新方法.基于多尺度小波变换在时/空域所具有的优异局部化特性,从复杂场景中提取前景运动对象,克服环境条件约束以及动态环境变化及先验假设等不足;基于多尺度小波变换的梯度积分图方法,获取稳定可靠的指势手部HOG特征,采用机器学习方法,对上述特征向量分类,并基于指势手与指势用户对象的空间关联性识别指势用户对象.通过实验对比,结果表明本文方法有效、可行.     

Research on unified recognition model and algorithm for multi-modal gestures

In gesture recognition,static gestures,dynamic gestures and trajectory gestures are collectively known as multi-modal gestures.To solve the existing problem in different recognition methods for different modal gestures,a unified recognition algorithm is proposed.The angle change data of the finger joints and the movement of the centroid of the hand were acquired respectively by data glove and Kinect.Through the preprocessing of the multi-source heterogeneous data,all hand gestures were considered as curves while solving hand shaking,and a uniform hand gesture recognition algorithm was established to calculate the Pearson correlation coefficient between hand gestures for gesture recognition.In this way,complex gesture recognition was transformed into the problem of a simple comparison of curves similarities.The main innovations:1) Aiming at solving the problem of multi-modal gesture recognition,an unified recognition model and a new algorithm is proposed;2) The Pearson correlation coefficient for the first time to construct the gesture similarity operator is improved.By testing 50 kinds of gestures,the experimental results showed that the method presented could cope with intricate gesture interaction with the 97.7% recognition rate.     

电视机手势遥控系统设计

提出了一种基于手势识别的交互方式用于遥控电视机,系统利用CMOS图像传感器捕捉用户手势信息,结合采集到的人手运动轨迹和手势识别技术,与标准手势的样本信息进行比对,从而判断出与之对应的控制信号,最后通过红外发射器完成对电视机各项基本功能的调控,实现了自然友好的人机交互操作,该系统使人们摆脱了传统的遥控器,可用于数字娱乐、...     

基于时空压缩特征表示学习的毫米波雷达手势识别算法

针对现有无线射频信号的手势识别研究中的数据预处理和特征利用问题,该文提出一种用于调频连续波(FMCW)雷达的时空压缩特征表示学习的手势识别算法。首先对手部反射的毫米波雷达回波信号的距离-多普勒(RD)图进行静态干扰去除和动目标点筛选,减少杂波对手势信号的干扰,同时减少计算数据量;然后提出一种压缩手势时空特征的表示方法,利用动目标点的主导速度来表示手势的运动特征,实现多维特征的压缩映射,并保留手势运动的关键特征信息;最后设计了一个单通道的卷积神经网络(CNN)来学习和分类多维手势特征信息并应用于多用户和多位置的手势识别。实验结果表明,与现有其他手势识别算法相比,该文提出的手势识别方法在识别精度、实时性以及泛化能力上都具有明显的优势。     

基于FMCW雷达的双流融合神经网络手势识别方法

针对传统光学摄像头和无线技术的手势识别方法受光照环境影响和空间纵向、横向特征不全的问题,该文提出一种基于调频连续波（Frequency Modulated Continuous Wave,FMCW）雷达信号的双流融合神经网络（Two-Stream Fusion Neural Network,TS-FNN）手势识别方法.首先,利用二维快速傅立叶变换（Fast Fourier Transform,FFT）求取中频信号的频谱,估计手势的距离和速度,并利用多重信号分类（Multiple Signal Classification,MUSIC）方法计算角度.其次,利用这三维参数在时间上的累积,将一个手势动作映射为32帧距离-速度矩阵图和角度时间图.最后,建立TS-FNN进行手势特征提取和特征融合.实验结果表明,TS-FNN方法与传统卷积神经网络相比,手势的平均识别准确率提升了约5%.     

一种基于距离相似性度量和HMMs的字符识别方法

为了能够综合利用隐马尔可夫模型（HMMs）分类器在分类过程中能够得到的多种信息,提出一种基于距离相似性度量对HMMs后验概率进行调整的方法,将样本相似性与HMMs后验概率有机地结合起来进行识别。在分类过程中,采用距离相似性度量来描述待识别样本与模式类标准样本间的相似性,然后采用归一化距离相似性度量对后验概率进行适当调整,最后用调整后的概率进行分类。实验结果表明：与标准的HMMs识别方法相比,改进后的方法能够在计算量增加很小的情况下,较好地改善系统的识别精度;系统性能的改善效率在1．1～6．5间。     

Steady state hierarchical optimizing control for large-scaleindustrial processes with fuzzy parameters

This paper presents a new method for steady state hierarchical optimizing control of large-scale industrial processes. Several classical steady state coordination mechanisms are applied to the case in which the model coefficients of each subprocess of a large-scale industrial process are replaced by fuzzy numbers. Hence, each subprocess model is converted into a fuzzy form and then the original crisp programming problem with equality and inequality constraints is transformed into the fuzzy programming problem with fuzzy equality and crisp inequality constraints in each local decision unit. The final solutions are obtained by solving the general mathematical programming problem after the fuzzy equality constraints are converted into crisp inequality constraints. The developed method is mainly used to deal with the model-reality difference caused by either the model coefficients of the subprocess not being known accurately or the model slowly varying during normal operation. Three main types of coordination for processes with fuzzy parameters are derived in this paper: interaction balance method (IBM), interaction prediction method (IPM), and mixed method (MM). Simulation results of two examples show that 1) the proposed method can deal with model-reality difference efficiently, 2) the convergence speed of the on-line coordination for fuzzy parameter processes is faster than that of corresponding coordination for crisp parameter processes, and 3) the objective function of real processes can be improved by using the proposed method compared with the classical case. Furthermore, the studies show that the interaction balance method with global feedback (IBMF) based on a double iterative technique for processes with fuzzy parameters is the coordination algorithm that requires the fewest number of on-line iterations so far     

Hand gesture understanding by weakly-supervised fusing shallow/deep image attributes

Accurately recognizing human hand gestures is a useful component in many modern intelligent systems, such as identification authentication, human–computer interaction, and sign language recognition. Conventional approaches are typically based on shallow visual features and relatively simple backgrounds, which cannot readily recognize partially occluded hand gestures with sophisticated backgrounds. In this work, we propose a unified hand gesture recognition framework by optimally fusing a set of shallow/deep finger-level image attributes, based on which a weakly-supervised ranking algorithm is designed to select semantically salient regions for gesture understanding. More specifically, given a rich number of hand gesture images, we employ the well-known BING object proposal generator to extract hundreds of object patches that potentially draw human visual attention. Since the hundreds of object patches are still too many for building an effective recognition system, a weakly-supervised metric is proposed to rank them by extracting multiple shallow/deep features. And visual semantics are encoded at region-level by transferring the image-level semantic tags into various human gesture image regions by a weakly-supervised learning paradigm Apparently, the top-ranking highly salient object patches are highly indicative to human visual perception of human hand gesture, Thus we extract their ImageNet-CNN features and further concatenate them. Finally, the concatenated deep feature is fed into a multi-class SVM for classifying each hand gesture image into a particular type. Comprehensive experimental validations have demonstrated the effectiveness and robustness of our proposed hybrid-feature-based hand gesture categorization.     

Unencumbered gestural interaction

Unencumbered hand gesture interfaces encompass both 3D interaction and 2D pointing. A model developed to study 3D interaction requires determining gestural strokes and hand motion dynamics and recognizing hand poses. Extended variable valued logic and a rule based induction algorithm contribute to inductive learning of hand gesture poses, yielding a recognition rate of 94 percent. FingerMouse, a freehand pointing system, detects pointing hand poses and tracks moving fingertips in close to real time     

基于自学习稀疏表示的动态手势识别方法

针对加速度传感器的手势采集方式提出一种基于自学习稀疏表示的动态手势识别方法。该方法将分类识别问题转化为求解待识别样本对于训练样本的稀疏表示问题,直接对原始加速度信号进行操作,省去了特征提取过程,可方便地添加新的手势类别和删除已有的手势类别;利用面向类别的字典学习,来寻求一个较小的并经过优化的超完备字典来计算待识别样本的稀疏表示,从而大大缩减算法的计算复杂度,满足实时性要求。在包含18种手势的3 000多个样本的公开数据集上进行测试,实验结果验证了该方法的有效性。     

Viewpoint-independent hand gesture recognition with Kinect

The advent and popularity of Kinect provide new choice and opportunity for hand gesture recognition research. Aiming at the effective, accurate and freely used hand gesture recognition with Kinect, this paper presents a viewpoint-independent hand gesture recognition method. Firstly, based on the rules about gesturers posture under optimal viewpoint, the gesturers point clouds are built and transformed to the optimal viewpoint with the exploration of the joint information. Then Laplacian-based contraction is applied to extract representative skeletons from the transformed point clouds. A novel partition-based algorithm is further proposed to recognize the gestures. The promising experiment results show that the proposed method performs satisfyingly on scale and rotation variant in HGR with robustness and high accuracy.     

A hand gesture recognition technique for human–computer interaction

We propose an approach to recognize trajectory-based dynamic hand gestures in real time for human–computer interaction (HCI). We also introduce a fast learning mechanism that does not require extensive training data to teach gestures to the system. We use a six-degrees-of-freedom position tracker to collect trajectory data and represent gestures as an ordered sequence of directional movements in 2D. In the learning phase, sample gesture data is filtered and processed to create gesture recognizers, which are basically finite-state machine sequence recognizers. We achieve online gesture recognition by these recognizers without needing to specify gesture start and end positions. The results of the conducted user study show that the proposed method is very promising in terms of gesture detection and recognition performance (73% accuracy) in a stream of motion. Additionally, the assessment of the user attitude survey denotes that the gestural interface is very useful and satisfactory. One of the novel parts of the proposed approach is that it gives users the freedom to create gesture commands according to their preferences for selected tasks. Thus, the presented gesture recognition approach makes the HCI process more intuitive and user specific.     

一种基于模糊规则的鲁棒语音识别方法

本文在丢失数据技术与声学后退技术的基础上,提出了一种基于模糊规则的鲁棒语音识别方法,首先根据先验知识或假定建立特征分量的可靠程度与其概率分布之间的模糊规则,识别时观察矢量的输出概率由一个基于规则的模糊逻辑系统来得到,并针对倒谱识别系统给出了一种具体的实现方法.实验结果表明,所提识别方法的性能显著优于丢失数据技术和声学后退技术.     

时空数据库中模糊实体间拓扑查询的研究

时空数据库中确定空间实体间拓扑查询的研究已日益成熟,但有关不确定实体即模糊实体间的拓扑分析和查询的研究不多。文中依据模糊学基本理论,结合复杂确定空间实体间拓扑关系推理规则,系统阐述模糊实体间的拓扑关系,并给出定量的模糊拓扑谓词。这必将有助于时空数据库拓扑查询系统的完善和发展。     

一种新的SAR欺骗式干扰性能评估方法

雷达欺骗式干扰性能评估是电子对抗领域的一个重要课题。现有评估技术都是基于某单一特征,评估结果比较片面。针对这一不足,提出一种基于目标识别与模糊综合评判的SAR欺骗式干扰性能评估方法,综合考虑目标识别系统可能应用的识别特征,利用模糊综合评判的方法对虚假目标图像的逼真度进行综合评判,然后考虑系统处理时间对干扰性能的影响,对综合评判结果进行修正,该方法具有一定的理论和现实意义。     

基于Kinect传感器的家电手势控制应用研究

为提高智能家电的人机交互性,研究实现了一种基于Kinect传感器的手势识别系统,用户通过该系统可手势控制电视的多种操作功能。对常见的三种动态手势识别算法进行分析对比后,结合应用需求,重点研究了动态手势识别DTW算法。基于Kinect for windows SDK获取的手势深度图像和骨骼图像数据,采用DTW算法进行识别,最后给出了程序实现。实验表明,该方法可实现多种电视控制功能,而且具有较好的实时性和准确性。     

基于多特征融合与支持向量机的手势识别

针对手势识别中人的手部特征描述易受到环境因素影响,手势识别率低等问题,并考虑到单个特征的局限性,提出了一种基于Hu矩和HOG特征融合的支持向量机手势识别新方法。该方法首先对处理后的手势图像提取局部的HOG特征,然后针对手势的轮廓提取全局Hu矩特征,再将两种特征融合成混合特征,并通过主成分分析法对混合特征进行降维形成最终分类特征,并将新特征输入到支持向量机中进行识别。实验表明,该方法具有较好的鲁棒性和较高的识别率。     

一种基于最大似然Hausdorff距离的手势识别算法

针对字母手势的检测和跟踪问题,文章提出一种基于最大似然准则Hausdorff距离的手势识别算法。该算法首先对字母手势图像进行二值化处理,并由字母手势图像的边缘信息中提取字母手势的关键点(指根和指尖);然后采用基于最大似然准则的Hausdorff距离对手势进行识别,搜索策略采用类似于Rucklidge提出的多分辨率搜索方法,在不影响成功率和目标定位精度的情况下,可以显著地缩短搜索时间。实验结果表明此方法可以较好地识别字母手势,同时对部分变形(旋转和缩放)手势也有良好的效果。