SVM

SVM
  • 文章类型: Journal Article
    在过去的25年里,快速的城市化导致喀布尔省的土地利用和土地覆盖(LULC)发生了重大变化,阿富汗。为了评估LULC变化对地表温度(LST)的影响,喀布尔省使用1998年至2022年的Landsat卫星图像应用支持向量机(SVM)算法分为四个LULC类。使用来自热带的Landsat数据评估LST。应用细胞自动机-逻辑回归(CA-LR)模型预测了2034年和2046年LULC和LST的未来模式。结果显示LULC类的显著变化,随着建成区面积增加约9.37%,而裸露的土壤和植被覆盖率下降了7.20%和2.35%,分别,从1998年到2022年。对年度LST的分析表明,建成区的平均LST最高,其次是裸露的土壤和植被。未来的模拟结果表明,预计到2034年和2046年,建成区面积将分别增加到17.08%和23.10%,比2022年的11.23%。同样,LST的模拟结果表明,到2034年和2046年,经历最高LST等级(≥32°C)的区域预计将分别增加到27.01%和43.05%,比2022年的11.21%。结果表明,随着建成区面积的增加和植被覆盖的减少,LST显著增加,揭示了城市化和气温上升之间的直接联系。
    Over the past two and a half decades, rapid urbanization has led to significant land use and land cover (LULC) changes in Kabul province, Afghanistan. To assess the impact of LULC changes on land surface temperature (LST), Kabul province was divided into four LULC classes applying the Support Vector Machine (SVM) algorithm using the Landsat satellite images from 1998 to 2022. The LST was assessed using Landsat data from the thermal band. The Cellular Automata-Logistic Regression (CA-LR) model was applied to predict the future patterns of LULC and LST for 2034 and 2046. Results showed significant changes in LULC classes, as the built-up areas increased about 9.37%, while the bare soil and vegetation cover decreased 7.20% and 2.35%, respectively, from 1998 to 2022. The analysis of annual LST revealed that built-up areas showed the highest mean LST, followed by bare soil and vegetation. The future simulation results indicate an expected increase in built-up areas to 17.08% and 23.10% by 2034 and 2046, respectively, compared to 11.23% in 2022. Similarly, the simulation results for LST indicated that the area experiencing the highest LST class (≥ 32 °C) is expected to increase to 27.01% and 43.05% by 2034 and 2046, respectively, compared to 11.21% in 2022. The results indicate that LST increases considerably as built-up areas increase and vegetation cover decreases, revealing a direct link between urbanization and rising temperatures.
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  • 文章类型: Journal Article
    背景:经颅磁刺激(TMS)是一种评估运动皮质和皮质-肌肉通路功能的有价值的技术。TMS激活皮层中的运动神经元,在沿着皮质-肌肉途径传播后,可以测量为运动诱发电位(MEP)。TMS线圈的位置和取向以及用于递送TMS脉冲的强度被认为是影响MEP的存在/不存在的中心TMS设置参数。
    方法:我们试图使用机器学习从TMS设置参数预测MEP的存在。我们使用学科内或学科间的设计来训练不同的机器学习者。
    结果:我们获得了平均77%和65%的预测精度,在受试者内部和受试者之间的最大值高达90%和72%,分别。全盘,套袋集合似乎是预测MEP存在的最合适方法。
    结论:尽管在受试者中,通过基于TMS设置参数的机器学习来预测MEP可能是可行的,受试者之间的准确性有限,这表明将这种方法转移到实验或临床研究中带来了巨大的挑战。
    BACKGROUND: Transcranial magnetic stimulation (TMS) is a valuable technique for assessing the function of the motor cortex and cortico-muscular pathways. TMS activates the motoneurons in the cortex, which after transmission along cortico-muscular pathways can be measured as motor-evoked potentials (MEPs). The position and orientation of the TMS coil and the intensity used to deliver a TMS pulse are considered central TMS setup parameters influencing the presence/absence of MEPs.
    METHODS: We sought to predict the presence of MEPs from TMS setup parameters using machine learning. We trained different machine learners using either within-subject or between-subject designs.
    RESULTS: We obtained prediction accuracies of on average 77 % and 65 % with maxima up to up to 90 % and 72 % within and between subjects, respectively. Across the board, a bagging ensemble appeared to be the most suitable approach to predict the presence of MEPs.
    CONCLUSIONS: Although within a subject the prediction of MEPs via TMS setup parameter-based machine learning might be feasible, the limited accuracy between subjects suggests that the transfer of this approach to experimental or clinical research comes with significant challenges.
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  • 文章类型: Journal Article
    中耳炎(OM),全世界儿童中非常普遍的炎症性中耳疾病,通常是由感染引起的,并可在复发性/慢性OM病例中导致抗生素抗性细菌生物膜。与OM相关的生物膜通常包含一种或多种细菌物种。OCT已在临床上用于可视化中耳中细菌生物膜的存在。本研究使用OCT比较细菌生物膜的微结构图像纹理特征。所提出的方法应用了基于监督机器学习的框架(SVM,随机森林,和XGBoost)对来自体外培养物的多种细菌生物膜和来自人类受试者的临床获得的体内图像进行分类。我们的研究结果表明,优化的SVM-RBF和XGBoost分类器实现了95%以上的AUC,检测每个生物膜类。这些结果表明,通过OCT图像的纹理分析和机器学习框架,可以区分OM引起的细菌生物膜。为耳部感染的实时体内表征提供有价值的见解。
    Otitis media (OM), a highly prevalent inflammatory middle-ear disease in children worldwide, is commonly caused by an infection, and can lead to antibiotic-resistant bacterial biofilms in recurrent/chronic OM cases. A biofilm related to OM typically contains one or multiple bacterial species. OCT has been used clinically to visualize the presence of bacterial biofilms in the middle ear. This study used OCT to compare microstructural image texture features from bacterial biofilms. The proposed method applied supervised machine-learning-based frameworks (SVM, random forest, and XGBoost) to classify multiple species bacterial biofilms from in vitro cultures and clinically-obtained in vivo images from human subjects. Our findings show that optimized SVM-RBF and XGBoost classifiers achieved more than 95% of AUC, detecting each biofilm class. These results demonstrate the potential for differentiating OM-causing bacterial biofilms through texture analysis of OCT images and a machine-learning framework, offering valuable insights for real-time in vivo characterization of ear infections.
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  • 文章类型: Journal Article
    先前的影像学研究表明,糖尿病性视网膜病变(DR)与大脑的结构和功能异常有关。然而,DR患者表现出异常神经血管偶联的程度仍在很大程度上未知.
    31名DR患者和31名性别和年龄匹配的健康对照者接受了静息状态功能磁共振成像(rs-fMRI)以计算功能连接强度(FCS)和动脉自旋标记成像(ASL)以计算脑血流量(CBF)。该研究比较了两组之间整个灰质的CBF-FCS耦合和每个体素的CBF/FCS比率(代表每单位连接强度的血液供应)。此外,采用支持向量机(SVM)方法区分糖尿病视网膜病变(DR)患者和健康对照(HC).
    与健康对照组相比,整个灰质的CBF-FCS耦合减少。具体来说,DR患者表现出主要在初级视觉皮层的CBF/FCS比值升高,包括右钙裂隙和周围皮质。另一方面,降低的CBF/FCS比率主要在电机前和辅助电机区域观察到,包括左额中回.
    CBF/FCS比值升高表明DR患者的脑灰质体积可能减少。其比率的降低表明DR患者的区域CBF降低。这些发现表明,视觉皮层中的神经血管去耦,以及辅助运动和额回,可能代表糖尿病视网膜病变的神经病理学机制。
    UNASSIGNED: Previous imaging studies have demonstrated that diabetic retinopathy (DR) is linked to structural and functional abnormalities in the brain. However, the extent to which DR patients exhibit abnormal neurovascular coupling remains largely unknown.
    UNASSIGNED: Thirty-one patients with DR and 31 sex- and age-matched healthy controls underwent resting-state functional magnetic resonance imaging (rs-fMRI) to calculate functional connectivity strength (FCS) and arterial spin-labeling imaging (ASL) to calculate cerebral blood flow (CBF). The study compared CBF-FCS coupling across the entire grey matter and CBF/FCS ratios (representing blood supply per unit of connectivity strength) per voxel between the two groups. Additionally, a support vector machine (SVM) method was employed to differentiate between diabetic retinopathy (DR) patients and healthy controls (HC).
    UNASSIGNED: In DRpatients compared to healthy controls, there was a reduction in CBF-FCS coupling across the entire grey matter. Specifically, DR patients exhibited elevated CBF/FCS ratios primarily in the primary visual cortex, including the right calcarine fissure and surrounding cortex. On the other hand, reduced CBF/FCS ratios were mainly observed in premotor and supplementary motor areas, including the left middle frontal gyrus.
    UNASSIGNED: An elevated CBF/FCS ratio suggests that patients with DR may have a reduced volume of gray matter in the brain. A decrease in its ratio indicates a decrease in regional CBF in patients with DR. These findings suggest that neurovascular decoupling in the visual cortex, as well as in the supplementary motor and frontal gyrus, may represent a neuropathological mechanism in diabetic retinopathy.
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  • 文章类型: Journal Article
    在建筑物的建造和拆除阶段,需要数据来做出有关管理废物的明智决策。然而,在大多数发展中国家,废物产生领域的数据可用性非常有限。这项研究的目的是采用基于人工智能(AI)的方法来开发可靠的模型,以预测德黑兰案例研究中的每月建筑和拆除废物(C&DW)生成。伊朗。我们使用各种AI算法训练了不同的预测模型,包括多层感知器神经网络,径向基函数神经网络,支持向量机,和自适应神经模糊推理系统(ANFIS)。根据调查结果,所有采用的人工智能算法对C&DW预测模型都表现出很高的预测性能。ANFIS模型,R2=0.96和RMSE=0.04209,被确定为更好地代表C和DW代的观察值的模型。ANFIS模型的更好效率可能是由于其有效增强了神经网络以基于模糊逻辑能力对主观变量进行建模。通过预测未来的废物数量,可以将开发的预测模型用作C&DW管理的政策和决策的有效工具。
    Data is needed for making informed decisions regarding managing waste in the time of construction and demolition phases of buildings. However, data availability is very limited in most developing countries in the area of waste generation. The objective of this study is to employ an artificial intelligence (AI)-based approach to develop a reliable model for forecasting monthly construction and demolition waste (C&DW) generation in the case study of Tehran, Iran. We have trained different prediction models using various AI algorithms, including multilayer perceptron neural network, radial basis function neural network, support vector machines, and adaptive neuro-fuzzy inference system (ANFIS). According to the findings, all employed AI algorithms demonstrated high prediction performance for C&DW forecasting models. The ANFIS model, with R2 = 0.96 and RMSE = 0.04209, was identified as the model that better represented the observed values of C&DW generation. The better efficiency of the ANFIS model could be due to its effective enhancement of neural networks to model subjective variables based on fuzzy logic capabilities. The developed prediction model can be employed as an efficient tool for policy and decision-making for C&DW management by predicting waste quantities in the future.
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  • 文章类型: Journal Article
    高效的交通系统对于智慧城市的发展至关重要。自动驾驶汽车和智能交通系统(ITS)是此类系统的关键组成部分,有助于安全,可靠,可持续交通。它们可以减少交通拥堵,改善交通流量,加强道路安全,从而使城市交通更加高效和环保。我们提出了光子雷达技术和支持向量机分类的创新组合,旨在改善复杂交通场景下的多目标检测。我们方法的核心是调频连续波光子雷达,用空间复用增强,能够在各种环境条件下识别多个目标,包括具有挑战性的天气。值得注意的是,我们的系统实现了7厘米的令人印象深刻的范围分辨率,即使在恶劣的天气条件下,利用4GHz的工作带宽。此功能对于动态交通环境中的精确检测和分类尤为重要。雷达系统的低功耗要求和紧凑的设计增强了其在自动驾驶汽车中的部署适用性。通过全面的数值模拟,我们的系统展示了它在不同距离和运动状态下准确检测目标的能力,固定目标的分类精度为75%,移动目标的分类精度为33%。这项研究通过为障碍物检测和分类提供复杂的解决方案,大大有助于ITS,从而提高自主车辆在城市环境中导航的安全性和效率。
    Efficient transportation systems are essential for the development of smart cities. Autonomous vehicles and Intelligent Transportation Systems (ITS) are crucial components of such systems, contributing to safe, reliable, and sustainable transportation. They can reduce traffic congestion, improve traffic flow, and enhance road safety, thereby making urban transportation more efficient and environmentally friendly. We present an innovative combination of photonic radar technology and Support Vector Machine classification, aimed at improving multi-target detection in complex traffic scenarios. Central to our approach is the Frequency-Modulated Continuous-Wave photonic radar, augmented with spatial multiplexing, enabling the identification of multiple targets in various environmental conditions, including challenging weather. Notably, our system achieves an impressive range resolution of 7 cm, even under adverse weather conditions, utilizing an operating bandwidth of 4 GHz. This feature is particularly crucial for precise detection and classification in dynamic traffic environments. The radar system\'s low power requirement and compact design enhance its suitability for deployment in autonomous vehicles. Through comprehensive numerical simulations, our system demonstrated its capability to accurately detect targets at varying distances and movement states, achieving classification accuracies of 75% for stationary and 33% for moving targets. This research substantially contributes to ITS by offering a sophisticated solution for obstacle detection and classification, thereby improving the safety and efficiency of autonomous vehicles navigating through urban environments.
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  • 文章类型: Journal Article
    通过利用机器学习技术进行疾病检测的研究一直受到关注。机器学习技术的使用对于及时发现重大疾病并提供适当的治疗非常重要。疾病检测是一项重要而敏感的任务,而机器学习模型可以提供强大的解决方案。他们可能会觉得复杂和不直观。因此,衡量对预测的更好理解和对结果的信任是很重要的。本文承担了皮肤病检测的关键任务,介绍了一种结合SVM和XGBoost的混合机器学习模型用于检测任务。所提出的模型优于现有的机器学习模型-支持向量机(SVM),决策树,和XGBoost,准确率为99.26%。由于症状的相似性,提高的准确性对于检测皮肤病至关重要,这使得区分不同状况具有挑战性。为了增进信任并深入了解结果,我们转向了可解释人工智能(XAI)的有前途的领域。我们探索了两个这样的框架,用于对这些机器学习模型进行局部和全局解释,即,沙普利加性扩张(SHAP)和局部可解释模型不可知解释(LIME)。
    Research on disease detection by leveraging machine learning techniques has been under significant focus. The use of machine learning techniques is important to detect critical diseases promptly and provide the appropriate treatment. Disease detection is a vital and sensitive task and while machine learning models may provide a robust solution, they can come across as complex and unintuitive. Therefore, it is important to gauge a better understanding of the predictions and trust the results. This paper takes up the crucial task of skin disease detection and introduces a hybrid machine learning model combining SVM and XGBoost for the detection task. The proposed model outperformed the existing machine learning models - Support Vector Machine (SVM), decision tree, and XGBoost with an accuracy of 99.26%. The increased accuracy is essential for detecting skin disease due to the similarity in the symptoms which make it challenging to differentiate between the different conditions. In order to foster trust and gain insights into the results we turn to the promising field of Explainable Artificial Intelligence (XAI). We explore two such frameworks for local as well as global explanations for these machine learning models namely, SHapley Additive exPlanations (SHAP) and Local Interpretable Model-agnostic Explanations (LIME).
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  • 文章类型: Journal Article
    微阵列基因表达数据由于其维度问题的诅咒而提出了巨大的挑战。功能的绝对数量远远超过可用的样品,导致过拟合和降低分类精度。因此,必须通过有效的特征提取方法来降低微阵列基因表达数据的维数,以减少数据量并提取有意义的信息,以提高分类准确性和可解释性。在这项研究中,我们发现了应用STFT(短期傅里叶变换)的唯一性,LASSO(最小绝对收缩和选择运算符),和EHO(大象放群优化),用于从肺癌中提取重要特征并降低微阵列基因表达数据库的维度。肺癌的分类使用以下分类器进行:高斯混合模型(GMM),基于GMM的粒子群优化算法(PSO),去趋势波动分析(DFA)朴素贝叶斯分类器(NBC),带GMM的萤火虫,径向基核支持向量机(SVM-RBF)和基于GMM的花授粉优化(FPO).使用FPO-GMM分类器的EHO特征提取在96.77的范围内获得了最高的准确性,F1得分为97.5,MCC为0.92,Kappa为0.92。报告的结果强调了利用STFT的重要性,拉索,和EHO用于特征提取,以降低微阵列基因表达数据的维数。这些方法还有助于改善和早期诊断肺癌,并提高分类准确性和可解释性。
    The microarray gene expression data poses a tremendous challenge due to their curse of dimensionality problem. The sheer volume of features far surpasses available samples, leading to overfitting and reduced classification accuracy. Thus the dimensionality of microarray gene expression data must be reduced with efficient feature extraction methods to reduce the volume of data and extract meaningful information to enhance the classification accuracy and interpretability. In this research, we discover the uniqueness of applying STFT (Short Term Fourier Transform), LASSO (Least Absolute Shrinkage and Selection Operator), and EHO (Elephant Herding Optimisation) for extracting significant features from lung cancer and reducing the dimensionality of the microarray gene expression database. The classification of lung cancer is performed using the following classifiers: Gaussian Mixture Model (GMM), Particle Swarm Optimization (PSO) with GMM, Detrended Fluctuation Analysis (DFA), Naive Bayes classifier (NBC), Firefly with GMM, Support Vector Machine with Radial Basis Kernel (SVM-RBF) and Flower Pollination Optimization (FPO) with GMM. The EHO feature extraction with the FPO-GMM classifier attained the highest accuracy in the range of 96.77, with an F1 score of 97.5, MCC of 0.92 and Kappa of 0.92. The reported results underline the significance of utilizing STFT, LASSO, and EHO for feature extraction in reducing the dimensionality of microarray gene expression data. These methodologies also help in improved and early diagnosis of lung cancer with enhanced classification accuracy and interpretability.
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  • 文章类型: Journal Article
    冬季恶劣天气下路面状况的准确检测对交通安全至关重要。为了促进安全驾驶和有效的道路管理,这项研究提出了一个准确和可推广的数据驱动的学习模型,用于估计路面状况。机器模型是支持向量机(SVM),已成功应用于各个领域,和核函数(线性,高斯,还采用了具有软边缘分类技术的二阶多项式)。两种学习者设计(一对一,一对一)将其应用扩展到多类别分类。除了这个非概率分类器,这项研究通过将sigmoid函数应用于经训练的SVM获得的分类分数来计算属于每个组的后验概率。结果表明,所有分类器的分类误差,不包括一元对全线性学习器,低于3%,从而准确地对路面状况进行分类,并且所有一对一学习者的泛化性能都在4%的错误率之内。结果还表明,后验概率可以分析与危险路面条件的高概率相对应的某些大气和路面条件。因此,这项研究证明了数据驱动的学习模型在准确分类路面条件方面的潜力。
    Accurate detection of road surface conditions in adverse winter weather is essential for traffic safety. To promote safe driving and efficient road management, this study presents an accurate and generalizable data-driven learning model for the estimation of road surface conditions. The machine model was a support vector machine (SVM), which has been successfully applied in diverse fields, and kernel functions (linear, Gaussian, second-order polynomial) with a soft margin classification technique were also adopted. Two learner designs (one-vs-one, one-vs-all) extended their application to multi-class classification. In addition to this non-probabilistic classifier, this study calculated the posterior probability of belonging to each group by applying the sigmoid function to the classification scores obtained by the trained SVM. The results indicate that the classification errors of all the classifiers, excluding the one-vs-all linear learners, were below 3%, thereby accurately classifying road surface conditions, and that the generalization performance of all the one-vs-one learners was within an error rate of 4%. The results also showed that the posterior probabilities can analyze certain atmospheric and road surface conditions that correspond to a high probability of hazardous road surface conditions. Therefore, this study demonstrates the potential of data-driven learning models in classifying road surface conditions accurately.
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  • 文章类型: Journal Article
    这项研究的目的是评估手持式近红外设备(900-1600nm)预测生育力和性别(男性和女性)特征的能力。在孵化的第0、7、14和18天收集卵样品的近红外反射光谱,并使用主成分分析(PCA)分析数据,线性判别分析(LDA)和支持向量机分类(SVM)。使用LDA和SVM分类,预测可育和不育卵样本的总体分类率在73%至84%之间,在93%至95%之间,分别。在孵育的第7天获得最高的分类率。雄性和雌性胚胎之间的分类实现了较低的分类率,使用LDA和SVM分类在62%到68%之间,分别。尽管在这项研究中获得的卵内性别分类率高于偶然获得的分类率(50%),分类结果目前不足以进行鸡蛋的工业卵内性别鉴定。这些结果表明,NIR范围内的短波长可能有助于区分孵化过程中第7天和第14天的可育和不育卵样品。
    The objective of this study was to evaluate the ability of a handheld near-infrared device (900-1600 nm) to predict fertility and sex (male and female) traits in-ovo. The NIR reflectance spectra of the egg samples were collected on days 0, 7, 14 and 18 of incubation and the data was analysed using principal component analysis (PCA), linear discriminant analysis (LDA) and support vector machines classification (SVM). The overall classification rates for the prediction of fertile and infertile egg samples ranged from 73 % to 84 % and between 93 % to 95 % using LDA and SVM classification, respectively. The highest classification rate was obtained on day 7 of incubation. The classification between male and female embryos achieved lower classification rates, between 62 % and 68 % using LDA and SVM classification, respectively. Although the classification rates for in-ovo sexing obtained in this study are higher than those obtained by chance (50 %), the classification results are currently not sufficient for industrial in-ovo sexing of chicken eggs. These results demonstrated that short wavelengths in the NIR range may be useful to distinguish between fertile and infertile egg samples at days 7 and 14 during incubation.
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