pattern recognition

模式识别
  • 文章类型: Journal Article
    基于证据理论(ET)的信念和可信性函数已广泛用于管理不确定性。文献中已经报道了ET对模糊集(FS)的各种推广,但目前还没有将ET推广到q-rung视界模糊集(q-ROFS)。因此,本文提出了一部小说,简单,以及基于ET框架内的信念和合理性函数的q-ROFS的距离和相似性度量的直观方法。这项研究通过引入一个全面的框架来使用ET处理q-ROFS中的不确定性,从而解决了一个重大的研究空白。此外,它承认当前研究状况固有的局限性,值得注意的是,没有将ET概括为q-ROFS,以及将信念和合理性度量扩展到某些聚合运算符和其他概括(包括Hesitant模糊集)的挑战,双极模糊集,模糊软集等。我们的贡献在于提出了一种新的方法,用于ET下q-ROFS的距离和相似性度量,利用正交信念和可信性间隔(OBPI)。我们在广义ET框架内建立了新的相似性度量,并通过有用的数值示例证明了我们方法的合理性。此外,我们构建了Orthopairian信念和合理性GRA(OBP-GRA)来管理日常生活中的复杂问题,特别是在多准则决策场景中。数值仿真和成果证实了我们提出的办法在ET框架下的可用性和现实适用性。
    Belief and plausibility functions based on evidence theory (ET) have been widely used in managing uncertainty. Various generalizations of ET to fuzzy sets (FSs) have been reported in the literature, but no generalization of ET to q-rung orthopair fuzzy sets (q-ROFSs) has been made yet. Therefore, this paper proposes a novel, simple, and intuitive approach to distance and similarity measures for q-ROFSs based on belief and plausibility functions within the framework of ET. This research addresses a significant research gap by introducing a comprehensive framework for handling uncertainty in q-ROFSs using ET. Furthermore, it acknowledges the limitations inherent in the current state of research, notably the absence of generalizations of ET to q-ROFSs and the challenges in extending belief and plausibility measures to certain aggregation operators and other generalizations including Hesitant fuzzy sets, Bipolar fuzzy sets, Fuzzy soft sets etc. Our contribution lies in the proposal of a novel approach to distance and similarity measures for q-ROFSs under ET, utilizing Orthopairian belief and plausibility intervals (OBPIs). We establish new similarity measures within the generalized ET framework and demonstrate the reasonability of our method through useful numerical examples. Additionally, we construct Orthopairian belief and plausibility GRA (OBP-GRA) for managing daily life complex issues, particularly in multicriteria decision-making scenarios. Numerical simulations and results confirm the usability and practical applicability of our proposed method in the framework of ET.
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  • 文章类型: Journal Article
    普什图语是东南亚使用最广泛的语言之一。PashtuNumerics识别由于其草书性质而面临挑战。尽管如此,采用基于机器学习的光学字符识别(OCR)模型可以是解决这个问题的有效方法。该研究的主要目的是提出一种优化的机器学习模型,该模型可以有效地识别0-9的Pashtu数字。该方法包括将数据组织到每个表示标签的不同目录中。之后,数据经过预处理,即图像大小调整为32×32图像,然后将它们的像素值除以255进行归一化,并为模型输入重新整形数据。数据集以80:20的比例分割。在这之后,在试错技术的帮助下,为LSTM和CNN模型选择优化的超参数。通过准确性和损失图对模型进行了评估,分类报告,和混乱矩阵。结果表明,所提出的LSTM模型略微优于所提出的CNN模型,具有精度的宏观平均值:0.9877,召回率:0.9876,F1得分:0.9876。这两个模型在准确识别普什图数字方面都表现出卓越的性能,达到近98%的准确率。值得注意的是,在这方面,LSTM模型比CNN模型表现出边际优势。
    Pashtu is one of the most widely spoken languages in south-east Asia. Pashtu Numerics recognition poses challenges due to its cursive nature. Despite this, employing a machine learning-based optical character recognition (OCR) model can be an effective way to tackle this issue. The main aim of the study is to propose an optimized machine learning model which can efficiently identify Pashtu numerics from 0-9. The methodology includes data organizing into different directories each representing labels. After that, the data is preprocessed i.e., images are resized to 32 × 32 images, then they are normalized by dividing their pixel value by 255, and the data is reshaped for model input. The dataset was split in the ratio of 80:20. After this, optimized hyperparameters were selected for LSTM and CNN models with the help of trial-and-error technique. Models were evaluated by accuracy and loss graphs, classification report, and confusion matrix. The results indicate that the proposed LSTM model slightly outperforms the proposed CNN model with a macro-average of precision: 0.9877, recall: 0.9876, F1 score: 0.9876. Both models demonstrate remarkable performance in accurately recognizing Pashtu numerics, achieving an accuracy level of nearly 98%. Notably, the LSTM model exhibits a marginal advantage over the CNN model in this regard.
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  • 文章类型: Journal Article
    作为人工嗅觉的信息采集终端,化学电阻式气体传感器经常被它们的交叉灵敏度所困扰,降低其对环境气体的交叉响应一直是气体传感领域的难点和重点。基于传感器阵列的模式识别是克服气体传感器交叉敏感性的最明显方法。选择合适的模式识别方法对增强数据分析至关重要,减少错误,提高系统可靠性,获得较好的分类或气体浓度预测结果。在这次审查中,分析了化学电阻式气体传感器交叉敏感的传感机理。我们进一步检查类型,工作原理,特点,以及在气体传感阵列中使用的模式识别算法的适用气体检测范围。此外,我们报告,总结,并评估用于气体识别的模式识别方法的杰出和新颖的进步。同时,这项工作展示了利用这些方法进行气体识别的最新进展,特别是在三个关键领域:确保食品安全,监测环境,并协助医疗诊断.总之,本研究通过考虑现有的景观和挑战,预测未来的研究前景。希望这项工作将为减轻气体敏感设备中的交叉敏感性做出积极贡献,并为气体识别应用中的算法选择提供有价值的见解。
    As information acquisition terminals for artificial olfaction, chemiresistive gas sensors are often troubled by their cross-sensitivity, and reducing their cross-response to ambient gases has always been a difficult and important point in the gas sensing area. Pattern recognition based on sensor array is the most conspicuous way to overcome the cross-sensitivity of gas sensors. It is crucial to choose an appropriate pattern recognition method for enhancing data analysis, reducing errors and improving system reliability, obtaining better classification or gas concentration prediction results. In this review, we analyze the sensing mechanism of cross-sensitivity for chemiresistive gas sensors. We further examine the types, working principles, characteristics, and applicable gas detection range of pattern recognition algorithms utilized in gas-sensing arrays. Additionally, we report, summarize, and evaluate the outstanding and novel advancements in pattern recognition methods for gas identification. At the same time, this work showcases the recent advancements in utilizing these methods for gas identification, particularly within three crucial domains: ensuring food safety, monitoring the environment, and aiding in medical diagnosis. In conclusion, this study anticipates future research prospects by considering the existing landscape and challenges. It is hoped that this work will make a positive contribution towards mitigating cross-sensitivity in gas-sensitive devices and offer valuable insights for algorithm selection in gas recognition applications.
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  • 文章类型: Journal Article
    考古陶瓷最常见的科学分析旨在确定原材料来源和/或生产技术。科学家和考古学家广泛使用基于XRF的技术作为出处研究的工具。进行XRF分析后,除了解释和结论外,通常还使用多变量分析来分析结果。各种多元技术已经应用于考古陶瓷物源研究,以揭示不同的原材料来源,识别进口件,或确定不同的生产配方。这项研究旨在评估在史前各个时期定居在同一地区的三种文化中的陶瓷起源研究中的多变量分析结果。使用便携式能量色散X射线荧光光谱法(pEDXRF)来确定陶瓷材料的元素组成。以两种不同的方式制备陶瓷材料。将陶瓷体材料磨成粉末,均质化,然后压成片剂。之后,相同的碎片在合适的地方抛光。对片剂和抛光片进行定量和定性分析。对结果进行了无监督和有监督的多变量分析。根据结果,结论是,使用EDXRF光谱法对精心准备的碎片表面进行定性分析可用于来源研究,即使陶瓷组件是由类似的原材料制成的。
    The most common scientific analysis of archaeological ceramics aims to determine the raw material source and/or production technology. Scientists and archaeologists widely use XRF-based techniques as a tool in a provenance study. After conducting XRF analysis, the results are often analyzed using multivariate analysis in addition to interpretation and conclusions. Various multivariate techniques have already been applied in archaeological ceramics provenance studies to reveal different raw material sources, identify imported pieces, or determine different production recipes. This study aims to evaluate the results of multivariate analysis in the provenance study of ceramics that belong to three cultures that settled in the same area during various prehistoric periods. Portable energy-dispersive X-ray fluorescence spectrometry (pEDXRF) was used to determine the elemental composition of the ceramic material. The ceramic material was prepared in two different ways. The ceramic body material was ground into powder, homogenized, and then pressed into tablets. After that, the same fragments are polished in suitable places. Quantitative and qualitative analyses were performed on the tablets and polished pieces. The results were subjected to both unsupervised and supervised multivariate analysis. Based on the results, it was concluded that qualitative analysis of the well-prepared shards\' surface using EDXRF spectrometry could be utilized in provenance studies, even when the ceramic assemblages were made of similar raw materials.
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  • 文章类型: Journal Article
    超高频(UHF)感测是评估电力变压器绝缘系统质量的最有前途的技术之一,因为它能够通过检测发射的UHF信号来识别局部放电(PD)等故障。然而,在测量中应评估的频率范围仍然存在不确定性。例如,大多数出版物都指出,UHF辐射范围高达3GHz。然而,Cigré手册显示,最佳频谱在100MHz至1GHz之间,最近,一项研究表明,最佳频率范围在400兆赫和900兆赫之间。由于不同的故障需要不同的维护措施,科学和工业都在开发允许故障类型识别的系统。因此,值得注意的是,带宽减少可能会损害分类系统,尤其是那些基于频率的。本文结合了电力变压器的三个运行条件(健康状态,电弧故障,和套管上的局部放电)具有三种不同的自组织图,以进行故障分类:彩色技术(CT),主成分分析(PCA),和形状分析聚类技术(SACT)。对于每种情况,超高频信号的频率内容选择在三个频带:全频谱,Cigré小册子系列,在400MHz和900MHz之间。因此,这项工作的贡献是评估频谱限制如何改变故障分类,并根据UHF信号的频率内容评估信号处理方法的有效性。此外,这项工作的一个优点是它不像一些基于机器学习的方法那样依赖于训练。结果表明,降低的频率范围不是对电力变压器运行条件状态进行分类的限制因素。因此,有可能使用较低的频率范围,例如从400MHz到900MHz,有助于开发成本较低的数据采集系统。此外,尽管减少了频带信息,但发现PCA是最有前途的技术。
    Ultrahigh-frequency (UHF) sensing is one of the most promising techniques for assessing the quality of power transformer insulation systems due to its capability to identify failures like partial discharges (PDs) by detecting the emitted UHF signals. However, there are still uncertainties regarding the frequency range that should be evaluated in measurements. For example, most publications have stated that UHF emissions range up to 3 GHz. However, a Cigré brochure revealed that the optimal spectrum is between 100 MHz and 1 GHz, and more recently, a study indicated that the optimal frequency range is between 400 MHz and 900 MHz. Since different faults require different maintenance actions, both science and industry have been developing systems that allow for failure-type identification. Hence, it is important to note that bandwidth reduction may impair classification systems, especially those that are frequency-based. This article combines three operational conditions of a power transformer (healthy state, electric arc failure, and partial discharges on bushing) with three different self-organized maps to carry out failure classification: the chromatic technique (CT), principal component analysis (PCA), and the shape analysis clustering technique (SACT). For each case, the frequency content of UHF signals was selected at three frequency bands: the full spectrum, Cigré brochure range, and between 400 MHz and 900 MHz. Therefore, the contributions of this work are to assess how spectrum band limitation may alter failure classification and to evaluate the effectiveness of signal processing methodologies based on the frequency content of UHF signals. Additionally, an advantage of this work is that it does not rely on training as is the case for some machine learning-based methods. The results indicate that the reduced frequency range was not a limiting factor for classifying the state of the operation condition of the power transformer. Therefore, there is the possibility of using lower frequency ranges, such as from 400 MHz to 900 MHz, contributing to the development of less costly data acquisition systems. Additionally, PCA was found to be the most promising technique despite the reduction in frequency band information.
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  • 文章类型: Journal Article
    共生菌的生物固氮(BNF)在可持续农业中发挥着重要作用。然而,当前的量化方法通常是昂贵且不切实际的。这项研究探索了拉曼光谱的潜力,一种非侵入性技术,用于快速评估大豆中的BNF活性。从有和没有根瘤菌生长的大豆植物获得拉曼光谱,以鉴定与BNF相关的光谱特征。δN15同位素比质谱(IRMS)用于确定实际的BNF百分比。采用偏最小二乘回归(PLSR)来建立基于拉曼光谱的BNF定量模型。该模型解释了80%的BNF活性变异。为了增强模型对BNF检测的特异性,无论氮的可用性如何,随后实施了弹性网(Enet)正则化策略。这种方法提供了与大豆中BNF相关的关键波数和生物化学物质的见解。
    Biological nitrogen fixation (BNF) by symbiotic bacteria plays a vital role in sustainable agriculture. However, current quantification methods are often expensive and impractical. This study explores the potential of Raman spectroscopy, a non-invasive technique, for rapid assessment of BNF activity in soybeans. Raman spectra were obtained from soybean plants grown with and without rhizobia bacteria to identify spectral signatures associated with BNF. δN15 isotope ratio mass spectrometry (IRMS) was used to determine actual BNF percentages. Partial least squares regression (PLSR) was employed to develop a model for BNF quantification based on Raman spectra. The model explained 80% of the variation in BNF activity. To enhance the model\'s specificity for BNF detection regardless of nitrogen availability, a subsequent elastic net (Enet) regularisation strategy was implemented. This approach provided insights into key wavenumbers and biochemicals associated with BNF in soybeans.
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  • 文章类型: Journal Article
    基于模式识别(PR)的肌电控制系统可以自然地提供对上肢假肢的多功能和直观控制,并恢复失去的肢体功能,但是了解它们的稳健性仍然是一个悬而未决的科学问题。这项研究调查了肢体位置和电极移位-已提出的导致分类恶化的两个因素如何通过使用每个因素作为一个类别并计算可重复性和修改的可分离性指数来量化类别分布的变化来影响分类器的性能。十名肢体完整的参与者参加了这项研究。使用线性判别分析(LDA)作为分类器。结果证实了先前的研究,肢体位置和电极移位会降低分类性能(降低14-21%),因素之间没有差异(p>0.05)。当将肢体位置和电极移位视为类别时,我们可以对它们进行分类,单个和所有运动的准确率为96.13±1.44%和65.40±8.23%,分别。对五名截肢者的测试证实了上述发现。我们已经证明,每个因素都会引入特征空间中的变化,这些变化在统计上是新的类实例。因此,当在两个不同的肢体位置或电极移位中收集相同的运动时,特征空间包含两个统计上可分类的聚类。我们的结果是在理解PR方案对假肢肌电控制的挑战方面向前迈出了一步,需要对更多与截肢者相关的数据集进行进一步的验证。
    Pattern recognition (PR)-based myoelectric control systems can naturally provide multifunctional and intuitive control of upper limb prostheses and restore lost limb function, but understanding their robustness remains an open scientific question. This study investigates how limb positions and electrode shifts-two factors that have been suggested to cause classification deterioration-affect classifiers\' performance by quantifying changes in the class distribution using each factor as a class and computing the repeatability and modified separability indices. Ten intact-limb participants took part in the study. Linear discriminant analysis (LDA) was used as the classifier. The results confirmed previous studies that limb positions and electrode shifts deteriorate classification performance (14-21% decrease) with no difference between factors (p > 0.05). When considering limb positions and electrode shifts as classes, we could classify them with an accuracy of 96.13 ± 1.44% and 65.40 ± 8.23% for single and all motions, respectively. Testing on five amputees corroborated the above findings. We have demonstrated that each factor introduces changes in the feature space that are statistically new class instances. Thus, the feature space contains two statistically classifiable clusters when the same motion is collected in two different limb positions or electrode shifts. Our results are a step forward in understanding PR schemes\' challenges for myoelectric control of prostheses and further validation needs be conducted on more amputee-related datasets.
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  • 文章类型: Journal Article
    生物信息学的一个扩展领域是通过对生物医学特征进行分类的医学诊断。通过机器学习(ML)方法来提高诊断能力的自动医疗策略具有挑战性。他们需要对其性能进行正式检查,以确定增强ML方法的最佳条件。这项工作提出了基于多种自动调整监督机器学习技术的VotingandStacking(VC和SC)集成策略的变体,以提高传统基线分类器自动诊断脊柱骨科疾病的功效。集成策略是通过首先组合一组完整的基于不同过程的自动调谐基线分类器来创建的,如几何,概率,逻辑,和优化。接下来,三个最有前途的分类器在k-最近邻居(kNN)中选择,朴素贝叶斯(NB),逻辑回归(LR),线性判别分析(LDA),二次判别分析(QDA),支持向量机(SVM)人工神经网络(ANN),决策树(DT)。网格搜索K-Fold交叉验证策略用于自动调整基线分类器超参数。所提出的集成策略的性能独立地与自动调谐的基线分类器进行比较。简洁的分析评估准确性,精度,召回,F1分数,和ROC-ACU指标。分析还检查了错误分类的疾病元素,以找到针对此特定医学问题的最可靠和最不可靠的分类器。结果表明,VC集成策略提供了与最佳基线分类器(kNN)相当的改进。同时,当所有基线分类器都包含在SC集成中时,该策略在所有评估指标中超过95%,突出作为分类脊柱疾病的最合适的选择。
    One expanding area of bioinformatics is medical diagnosis through the categorization of biomedical characteristics. Automatic medical strategies to boost the diagnostic through machine learning (ML) methods are challenging. They require a formal examination of their performance to identify the best conditions that enhance the ML method. This work proposes variants of the Voting and Stacking (VC and SC) ensemble strategies based on diverse auto-tuning supervised machine learning techniques to increase the efficacy of traditional baseline classifiers for the automatic diagnosis of vertebral column orthopedic illnesses. The ensemble strategies are created by first combining a complete set of auto-tuned baseline classifiers based on different processes, such as geometric, probabilistic, logic, and optimization. Next, the three most promising classifiers are selected among k-Nearest Neighbors (kNN), Naïve Bayes (NB), Logistic Regression (LR), Linear Discriminant Analysis (LDA), Quadratic Discriminant Analysis (QDA), Support Vector Machine (SVM), Artificial Neural Networks (ANN), and Decision Tree (DT). The grid-search K-Fold cross-validation strategy is applied to auto-tune the baseline classifier hyperparameters. The performances of the proposed ensemble strategies are independently compared with the auto-tuned baseline classifiers. A concise analysis evaluates accuracy, precision, recall, F1-score, and ROC-ACU metrics. The analysis also examines the misclassified disease elements to find the most and least reliable classifiers for this specific medical problem. The results show that the VC ensemble strategy provides an improvement comparable to that of the best baseline classifier (the kNN). Meanwhile, when all baseline classifiers are included in the SC ensemble, this strategy surpasses 95% in all the evaluated metrics, standing out as the most suitable option for classifying vertebral column diseases.
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  • 文章类型: Journal Article
    听力障碍人群缺乏有效的早期手语学习框架可能会造成创伤性后果,在工作场所造成社会孤立和不公平待遇。字母和数字检测方法一直是早期手语学习的基本框架,但受到性能和准确性的限制。很难在现实生活中发现迹象。本文提出了一种基于YouOnlyLookOnce8.0(YOLOv8)算法的早期手语学习者的改进手语检测方法,称为智能手语检测系统(iSDS),它利用深度学习的力量来检测手语的独特特征。iSDS方法可以克服假阳性率,提高手语检测的准确性和速度。针对早期手语学习者提出的iSDS框架包括三个基本步骤:(i)图像像素处理,以提取在框架中表现不足的特征,(ii)使用YOLOv8的相互依赖的基于像素的特征提取,(iii)基于网络的签名者独立性验证。所提出的iSDS可实现更快的响应时间,并减少错误解释和推理延迟时间。iSDS的精度达到了超过97%的最先进的性能,召回,和F1得分,最佳mAP为87%。提出的iSDS方法有几个潜在的应用,包括连续手语检测系统和基于网络的智能手语识别系统。
    Lack of an effective early sign language learning framework for a hard-of-hearing population can have traumatic consequences, causing social isolation and unfair treatment in workplaces. Alphabet and digit detection methods have been the basic framework for early sign language learning but are restricted by performance and accuracy, making it difficult to detect signs in real life. This article proposes an improved sign language detection method for early sign language learners based on the You Only Look Once version 8.0 (YOLOv8) algorithm, referred to as the intelligent sign language detection system (iSDS), which exploits the power of deep learning to detect sign language-distinct features. The iSDS method could overcome the false positive rates and improve the accuracy as well as the speed of sign language detection. The proposed iSDS framework for early sign language learners consists of three basic steps: (i) image pixel processing to extract features that are underrepresented in the frame, (ii) inter-dependence pixel-based feature extraction using YOLOv8, (iii) web-based signer independence validation. The proposed iSDS enables faster response times and reduces misinterpretation and inference delay time. The iSDS achieved state-of-the-art performance of over 97% for precision, recall, and F1-score with the best mAP of 87%. The proposed iSDS method has several potential applications, including continuous sign language detection systems and intelligent web-based sign recognition systems.
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  • 文章类型: Journal Article
    在智能家居中,专注于人类活动识别(HAR)的应用已经复苏,特别是在环境智能和辅助生活技术领域。然而,这些应用对在现实世界中运行的任何自动分析系统提出了许多重大挑战,比如可变性,稀疏,和传感器测量中的噪声。尽管最先进的HAR系统在应对其中一些挑战方面取得了长足的进步,它们受到实际限制:它们需要在自动识别之前对连续传感器数据流进行成功的预分割,即,他们假设在部署期间存在oracle,并且它能够识别跨离散传感器事件的感兴趣的时间窗口。为了克服这个限制,我们提出了一种新颖的图引导神经网络方法,通过学习传感器之间的显式共燃关系来执行活动识别。我们通过以数据驱动的方式学习表示智能家居中传感器网络的更具表现力的图结构来实现这一目标。我们的方法通过应用注意力机制和节点嵌入的分层池化将离散输入传感器测量映射到特征空间。我们通过在CASAS数据集上进行几个实验来证明我们提出的方法的有效性,这表明所得到的图引导神经网络在多个数据集上比智能家居中HAR的最先进方法更胜一筹。这些结果是有希望的,因为它们推动智能家居的HAR更接近现实世界的应用。
    There has been a resurgence of applications focused on human activity recognition (HAR) in smart homes, especially in the field of ambient intelligence and assisted-living technologies. However, such applications present numerous significant challenges to any automated analysis system operating in the real world, such as variability, sparsity, and noise in sensor measurements. Although state-of-the-art HAR systems have made considerable strides in addressing some of these challenges, they suffer from a practical limitation: they require successful pre-segmentation of continuous sensor data streams prior to automated recognition, i.e., they assume that an oracle is present during deployment, and that it is capable of identifying time windows of interest across discrete sensor events. To overcome this limitation, we propose a novel graph-guided neural network approach that performs activity recognition by learning explicit co-firing relationships between sensors. We accomplish this by learning a more expressive graph structure representing the sensor network in a smart home in a data-driven manner. Our approach maps discrete input sensor measurements to a feature space through the application of attention mechanisms and hierarchical pooling of node embeddings. We demonstrate the effectiveness of our proposed approach by conducting several experiments on CASAS datasets, showing that the resulting graph-guided neural network outperforms the state-of-the-art method for HAR in smart homes across multiple datasets and by large margins. These results are promising because they push HAR for smart homes closer to real-world applications.
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