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1.
根据火灾探测的特点,提出相应的模糊神经网络,论述综合处理多种火灾信号的模糊处理计算模型;针对具体应用,对网络结构进行了改进。由于模糊神经网络的自适应特性和推理过程易于理解的特点,它很适用于高层建筑这样的复杂环境,并可明显提高火灾探测的灵活性和准确性。  相似文献   

2.
Log anomaly detection is an important paradigm for system troubleshooting. Existing log anomaly detection based on Long Short-Term Memory (LSTM) networks is time-consuming to handle long sequences. Transformer model is introduced to promote efficiency. However, most existing Transformer-based log anomaly detection methods convert unstructured log messages into structured templates by log parsing, which introduces parsing errors. They only extract simple semantic feature, which ignores other features, and are generally supervised, relying on the amount of labeled data. To overcome the limitations of existing methods, this paper proposes a novel unsupervised log anomaly detection method based on multi-feature (UMFLog). UMFLog includes two sub-models to consider two kinds of features: semantic feature and statistical feature, respectively. UMFLog applies the log original content with detailed parameters instead of templates or template IDs to avoid log parsing errors. In the first sub-model, UMFLog uses Bidirectional Encoder Representations from Transformers (BERT) instead of random initialization to extract effective semantic feature, and an unsupervised hypersphere-based Transformer model to learn compact log sequence representations and obtain anomaly candidates. In the second sub-model, UMFLog exploits a statistical feature-based Variational Autoencoder (VAE) about word occurrence times to identify the final anomaly from anomaly candidates. Extensive experiments and evaluations are conducted on three real public log datasets. The results show that UMFLog significantly improves F1-scores compared to the state-of-the-art (SOTA) methods because of the multi-feature.  相似文献   

3.
This research is based on a mixed strategic typology, combining innovators of Miller and Roth (1994, “A Taxonomy of Manufacturing Strategies,” Management Science, 40 (3), 285–304) and defenders of Miles et al. (1978, “Organizational Strategy, Structure and Process,” Academy of Management Review, 3, 546–562) and supported by the perception–evaluation personality model of Jung (1923, Psychological Types, London, Routledge & Kegan). Leadership model having five underlying constructs—group cohesion, intellectual flexibility, leader cognitive styles, leadership styles and leadership roles—is identified and studied. At first, respondent firms from various sectors are classified as innovators and defenders. Second, the constructs are empirically tested on them. Important findings suggest that innovators have intuitive-feeling leaders and defenders have sensing-thinking leaders, two of the four personality types proposed by Jung (1923). It has also been found that innovators are higher in the degree of intellectual adjustment; in the idea generation and nurturant phase leaders exhibit intuitive-feeling personality style; concept creators also exhibit the same. These findings may be used in organizations for leadership building, finding out best candidate job-fit and organization-fit during recruitment, and also for training and development of the leaders.  相似文献   

4.
提出了一种结合模糊决策与贝叶斯方法的异常检测模型,该模型将系统中与安全相关的事件进行分类,并以模糊隶属度函数的形式给出各类事件发生异常的实时置信度。异常检测系统综合某时刻所有实时概率取值,做出贝叶斯决策。同简单使用阈值方法的贝叶斯入侵检测模型相比,采用了模糊概率赋值的贝叶斯异常检测模型,在提高对问题描述的精确性同时,由于它对多种类型安全相关事件提供支持而具有更好的适应性,可以更全面地对更复杂的系统行为进行建模。  相似文献   

5.
张立国  蒋轶轩  田广军 《计量学报》2021,42(11):1436-1442
由于飞行高度等原因,无人机图像在实际使用中目标尺寸普遍较小、特征信息不明显,使用现有的算法对其进行目标检测存在困难。因此,提出了基于多尺度融合的图像多目标检测方法,使用Faster R-CNN为基础框架,将不同层次的特征信息进行融合,再结合上下文信息,实现了对无人机图像小目标检测。使用VisDrone2019数据集对地面车辆进行目标检查,实验证明:无人机对地面车辆目标的检测达到了较好的结果,所使用算法的精度达到88%,与其它算法相比提升了3.8%以上。  相似文献   

6.
冯波  汤伟  曲蕴慧  佟永亮 《包装工程》2020,41(3):218-223
目的提高阈值法在纸病检测系统中的通用性。方法通过实验法获取不同时间段图像灰度数据,依据获取数据的时间段对图像灰度数据进行分类,求得相应时间段的灰度最大平均值、灰度最小平均值、总体灰度平均值以及灰度标准差,应用图表分析法对图像灰度的各种数据进行对比分析,总结出图像灰度变化规律,使用Visual studio 2015进行编程并验证。结果实验结果显示此方案可以较好地适应外界光线的变化,提高纸病检测系统的鲁棒性。结论基于模糊逻辑的纸病检测动态阈值设置方案,可以有效提高阈值法在纸病检测系统中的通用性。  相似文献   

7.
For BCI systems, it is important to have an accurate and less complex architecture to control a device with enhanced accuracy. In this paper, a novel methodology for more accurate detection of the hemodynamic response has been developed using a multimodal brain-computer interface (BCI). An integrated classifier has been developed for achieving better classification accuracy using two modalities. An integrated EEG-fNIRS-based vector-phase analysis (VPA) has been conducted. An open-source dataset collected at the Technische Universität Berlin, including simultaneous electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) signals of 26 healthy participants during n-back tests, has been used for this research. Instrumental and physiological noise removal has been done using preprocessing techniques followed by individually detecting activity in both modalities. With resting state threshold circle, VPA has been used to detect a hemodynamic response in fNIRS signals, whereas phase plots for EEG signals have been constructed using Hilbert Transform to detect the activity in each trial. Multiple threshold circles are drawn in the vector plane, where each circle is drawn after task completion in each trial of EEG signal. Finally, both processes are integrated into one vector-phase plot to get combined detection of hemodynamic response for activity. Results of this study illustrate that the combined EEG-fNIRS VPA yields considerably higher average classification accuracy, that is 91.35%, as compared to other classifiers such as support vector machine (SVM), convolutional neural networks (CNN), deep neural networks (DNN) and VPA (with dual-threshold circles) with classification accuracies 82%, 89%, 87% and 86% respectively. Outcomes of this research demonstrate that improved classification performance can be feasibly achieved using multimodal VPA for EEG-fNIRS hybrid data.  相似文献   

8.
The growth of cloud in modern technology is drastic by provisioning services to various industries where data security is considered to be common issue that influences the intrusion detection system (IDS). IDS are considered as an essential factor to fulfill security requirements. Recently, there are diverse Machine Learning (ML) approaches that are used for modeling effectual IDS. Most IDS are based on ML techniques and categorized as supervised and unsupervised. However, IDS with supervised learning is based on labeled data. This is considered as a common drawback and it fails to identify the attack patterns. Similarly, unsupervised learning fails to provide satisfactory outcomes. Therefore, this work concentrates on semi-supervised learning model known as Fuzzy based semi-supervised approach through Latent Dirichlet Allocation (F-LDA) for intrusion detection in cloud system. This helps to resolve the aforementioned challenges. Initially, LDA gives better generalization ability for training the labeled data. Similarly, to handle the unlabelled data, Fuzzy model has been adopted for analyzing the dataset. Here, pre-processing has been carried out to eliminate data redundancy over network dataset. In order to validate the efficiency of F-LDA towards ID, this model is tested under NSL-KDD cup dataset is a common traffic dataset. Simulation is done in MATLAB environment and gives better accuracy while comparing with benchmark standard dataset. The proposed F-LDA gives better accuracy and promising outcomes than the prevailing approaches.  相似文献   

9.
空间相关噪声下信源个数的聚类检测算法   总被引:2,自引:0,他引:2  
针对空间相关噪声情况,利用两个独立阵列之间噪声不相关的特性,采用联合协方差矩阵的规范相关系数作为聚类特征,提出了一种基于模糊c均值聚类的信源个数检测方法.并详细分析了应用Fuzzy-c-Means(FCM)聚类算法进行信源个数检测的3个问题: 聚类的趋势、有效性和聚类中心的初始化.与经典算法相比,本文算法有较好的角度分辨力和检测性能.仿真结果证明了该方法的有效性和鲁棒性.  相似文献   

10.
A new model is proposed in this paper on color edge detection that uses the second derivative operators and data fusion mechanism. The second-order neighborhood shows the connection between the current pixel and the surroundings of this pixel. This connection is for each RGB component color of the input image. Once the image edges are detected for the three primary colors: red, green, and blue, these colors are merged using the combination rule. Then, the final decision is applied to obtain the segmentation. This process allows different data sources to be combined, which is essential to improve the image information quality and have an optimal image segmentation. Finally, the segmentation results of the proposed model are validated. Moreover, the classification accuracy of the tested data is assessed, and a comparison with other current models is conducted. The comparison results show that the proposed model outperforms the existing models in image segmentation.  相似文献   

11.
MicroRNAs (miRNAs) are short, endogenous, noncoding RNAs that play critical roles in physiologic and pathologic processes and are vital biomarkers for several disease diagnostics and therapeutics. Therefore, rapid, low‐cost, sensitive, and selective detection of miRNAs is of paramount importance and has aroused increasing attention in the field of medical research. Among the various reported miRNA sensors, devices based on graphene and its derivatives, which form functional supramolecular nanoassemblies of π‐conjugated molecules, have been revealed to have great potential due to their extraordinary electrical, chemical, optical, mechanical, and structural properties. This Review critically and comprehensively summarizes the recent progress in miRNA detection based on graphene and its derivative materials, with an emphasis on i) the underlying working principles of these types of sensors, and the unique roles and advantages of graphene materials; ii) state‐of‐the‐art protocols recently developed for high‐performance miRNA sensing, including representative examples; and iii) perspectives and current challenges for graphene sensors. This Review intends to provide readers with a deep understanding of the design and future of miRNA detection devices.  相似文献   

12.
基于图像处理的轴类零件表面裂纹检测   总被引:2,自引:0,他引:2  
针对轴类零件表面图像的特点,提出一种基于图像处理的表面裂纹检测算法.算法首先采用空域和小波域混合滤波对图像去噪,提出一种图像分块自适应模糊集增强方法,以提高裂纹区和背景区的对比度;然后应用Canny边缘检测算子和数学形态学操作进行图像分割,提取裂纹区域;最后通过计算裂纹连通域的圆形度和长宽比特征判断零件的表面图像中是否有裂纹存在,实现裂纹检测.试验表明,该算法即使在信噪比不高的图像中也能实现对目标裂纹的检测,证明了算法的有效性.  相似文献   

13.
评价不同企业员工玩性人格对团队创新行为效率的影响程度。针对创新行为多方面输出、玩性人格多种类输入的特点,使用层次分析法(AHP)转化多种因素成相应的综合指标;利用数据包络分析(DEAP、编程排序)评价各个企业的综合创新行为效率。结果表明:长安、格力、海能达、华宇四个企业玩性人格控制较好,其他企业都处于规模报酬递增状态。在此基础上,以长安汽车作为标杆企业,对其他企业玩性人格的影响行为提出合理的对策,提高企业的创新行为  相似文献   

14.
基于模糊神经网络的液体火箭发动机振动检测   总被引:1,自引:0,他引:1  
液体火箭发动机振动检测涉及部件振动数据的收集、振动特征的抽取与度量以及度量结果的决策。基于模糊神经网络提出了一种发动机振动故障检测的基本系统。这种技术的吸引力在于:神经网络采用可变模糊集代表发动机工作模式,自然地提供了反映故障程度的有用信息;神经网络的离线学习算法可以从训练样本中提取振动知识;神经网络的监测算法不仅能正确预报故障,同时也能对新的振动信息进行在线学习。实验研究结果表明:模糊神经网络可以成功地用于泵压式液体火箭发动机热试车的振动故障检测。  相似文献   

15.
The development in Information and Communication Technology has led to the evolution of new computing and communication environment. Technological revolution with Internet of Things (IoTs) has developed various applications in almost all domains from health care, education to entertainment with sensors and smart devices. One of the subsets of IoT is Internet of Medical things (IoMT) which connects medical devices, hardware and software applications through internet. IoMT enables secure wireless communication over the Internet to allow efficient analysis of medical data. With these smart advancements and exploitation of smart IoT devices in health care technology there increases threat and malware attacks during transmission of highly confidential medical data. This work proposes a scheme by integrating machine learning approach and block chain technology to detect malware during data transmission in IoMT. The proposed Machine Learning based Block Chain Technology malware detection scheme (MLBCT-Mdetect) is implemented in three steps namely: feature extraction, Classification and blockchain. Feature extraction is performed by calculating the weight of each feature and reduces the features with less weight. Support Vector Machine classifier is employed in the second step to classify the malware and benign nodes. Furthermore, third step uses blockchain to store details of the selected features which eventually improves the detection of malware with significant improvement in speed and accuracy. ML-BCT-Mdetect achieves higher accuracy with low false positive rate and higher True positive rate.  相似文献   

16.
In recent years, the number of exposed vulnerabilities has grown rapidly and more and more attacks occurred to intrude on the target computers using these vulnerabilities such as different malware. Malware detection has attracted more attention and still faces severe challenges. As malware detection based traditional machine learning relies on exports’ experience to design efficient features to distinguish different malware, it causes bottleneck on feature engineer and is also time-consuming to find efficient features. Due to its promising ability in automatically proposing and selecting significant features, deep learning has gradually become a research hotspot. In this paper, aiming to detect the malicious payload and identify their categories with high accuracy, we proposed a packet-based malicious payload detection and identification algorithm based on object detection deep learning network. A dataset of malicious payload on code execution vulnerability has been constructed under the Metasploit framework and used to evaluate the performance of the proposed malware detection and identification algorithm. The experimental results demonstrated that the proposed object detection network can efficiently find and identify malicious payloads with high accuracy.  相似文献   

17.
Melanoma remains a serious illness which is a common form of skin cancer. Since the earlier detection of melanoma reduces the mortality rate, it is essential to design reliable and automated disease diagnosis model using dermoscopic images. The recent advances in deep learning (DL) models find useful to examine the medical image and make proper decisions. In this study, an automated deep learning based melanoma detection and classification (ADL-MDC) model is presented. The goal of the ADL-MDC technique is to examine the dermoscopic images to determine the existence of melanoma. The ADL-MDC technique performs contrast enhancement and data augmentation at the initial stage. Besides, the k-means clustering technique is applied for the image segmentation process. In addition, Adagrad optimizer based Capsule Network (CapsNet) model is derived for effective feature extraction process. Lastly, crow search optimization (CSO) algorithm with sparse autoencoder (SAE) model is utilized for the melanoma classification process. The exploitation of the Adagrad and CSO algorithm helps to properly accomplish improved performance. A wide range of simulation analyses is carried out on benchmark datasets and the results are inspected under several aspects. The simulation results reported the enhanced performance of the ADL-MDC technique over the recent approaches.  相似文献   

18.
运动背景中的运动检测难度较大,背景运动补偿后差分以及分割光流场可实现动目标和背景的分离,差分前需进行鲁棒的背景估计,且差分后易出现空洞,而光流估计在噪声以及目标运动速度较大时并不准确,尤其在光照变化时,两种方法均易失效。本文提出一种特征点位移矢量场模糊分割与图像自适应阈值化相结合的运动检测方法,实现在无任何关于运动目标或者运动背景先验信息条件下的动目标检测。通过改进的 SIFT匹配方法生成鲁棒的特征位移矢量场,采用模糊 C均值聚类算法对 SIFT位移矢量场进行无监督分类,实现动目标与背景特征的自适应分离。 OTSU法和形态学操作实现图像的自适应分割,用以修正特征点凸包,最终分割出动目标区域。与鲁棒的背景运动补偿后差分以及光流估计的对比实验表明,在目标运动速度较大、光照变化以及噪声情况下,本文方法均能够检测出运动目标,且在光照变化下的优势明显。  相似文献   

19.
一种红外图像序列弱小目标的检测方法   总被引:2,自引:1,他引:1  
针对低信噪比条件下红外弱小目标的相关检测算法存在的局限性,本文提出组合式相关检测算法.基于DBT的相关检测算法运算量小但检测性能较差,而基于TBD的相关检测算法检测性能较高但计算复杂.根据对两者优缺点的分析,采用将两种算法级联的方法,首先使用基于TBD的相关检测算法形成一个过渡帧,再以此为基础使用基于DBT的相关检测算法进行进一步检测.算法性能分析和实验结果均表明,低信噪比条件下该算法具有较高的检测性能并且计算量较低.  相似文献   

20.
This paper proposes a novel, efficient and affordable approach to detect the students’ engagement levels in an e-learning environment by using webcams. Our method analyzes spatiotemporal features of e-learners’ micro body gestures, which will be mapped to emotions and appropriate engagement states. The proposed engagement detection model uses a three-dimensional convolutional neural network to analyze both temporal and spatial information across video frames. We follow a transfer learning approach by using the C3D model that was trained on the Sports-1M dataset. The adopted C3D model was used based on two different approaches; as a feature extractor with linear classifiers and a classifier after applying fine-tuning to the pre-trained model. Our model was tested and its performance was evaluated and compared to the existing models. It proved its effectiveness and superiority over the other existing methods with an accuracy of 94%. The results of this work will contribute to the development of smart and interactive e-learning systems with adaptive responses based on users’ engagement levels.  相似文献   

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