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基于坐标注意力机制与Focal-EIOU的茶叶叶片病害检测 被引量:1
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作者 黎英涛 魏霖静 《软件工程》 2025年第2期10-15,共6页
针对复杂自然环境中茶叶病害的检测问题,提出一种创新的检测模型,旨在为茶叶病害的精确识别提供有力支持。模型设计中,增加了小目标检测层,提升了对微小目标的检测;引入了CA(CoordAttention)注意力机制,增强模型对细节信息的捕捉能力;采... 针对复杂自然环境中茶叶病害的检测问题,提出一种创新的检测模型,旨在为茶叶病害的精确识别提供有力支持。模型设计中,增加了小目标检测层,提升了对微小目标的检测;引入了CA(CoordAttention)注意力机制,增强模型对细节信息的捕捉能力;采用Focal-EIOU损失函数进一步优化算法模型;替换主干网络MobilevitV2,提升了模型的性能。实验结果表明,在同等条件下,与YOLOv8n原模型相比,本研究提出的优化算法实现了平均精度均值3.5百分点的提升,准确率达到91.6%。这些改进措施有效地提高了茶叶病害检测的准确率,而且为茶叶病害检测提供了坚实的理论基础和技术支撑。 展开更多
关键词 目标检测 注意力机制 损失函数 Yolov8n
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Position-aware packet loss optimization on service function chain placement
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作者 Wenjie Liang Chengxiang Li +1 位作者 Lin Cui Fung Po Tso 《Digital Communications and Networks》 SCIE CSCD 2024年第4期1057-1067,共11页
The advent of Network Function Virtualization(NFV)and Service Function Chains(SFCs)unleashes the power of dynamic creation of network services using Virtual Network Functions(VNFs).This is of great interest to network... The advent of Network Function Virtualization(NFV)and Service Function Chains(SFCs)unleashes the power of dynamic creation of network services using Virtual Network Functions(VNFs).This is of great interest to network operators since poor service quality and resource wastage can potentially hurt their revenue in the long term.However,the study shows with a set of test-bed experiments that packet loss at certain positions(i.e.,different VNFs)in an SFC can cause various degrees of resource wastage and performance degradation because of repeated upstream processing and transmission of retransmitted packets.To overcome this challenge,this study focuses on resource scheduling and deployment of SFCs while considering packet loss positions.This study developed a novel SFC packet dropping cost model and formulated an SFC scheduling problem that aims to minimize overall packet dropping cost as a Mixed-Integer Linear Programming(MILP)and proved that it is NP-hard.In this study,Palos is proposed as an efficient scheme in exploiting the functional characteristics of VNFs and their positions in SFCs for scheduling resources and deployment to optimize packet dropping cost.Extensive experiment results show that Palos can achieve up to 42.73%improvement on packet dropping cost and up to 33.03%reduction on average SFC latency when compared with two other state-of-the-art schemes. 展开更多
关键词 Network function virtualization Resource scheduling SFC deployment Packet loss
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An Improved Solov2 Based on Attention Mechanism and Weighted Loss Function for Electrical Equipment Instance Segmentation
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作者 Junpeng Wu Zhenpeng Liu +2 位作者 Xingfan Jiang Xinguang Tao Ye Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第1期677-694,共18页
The current existing problem of deep learning framework for the detection and segmentation of electrical equipment is dominantly related to low precision.Because of the reliable,safe and easy-to-operate technology pro... The current existing problem of deep learning framework for the detection and segmentation of electrical equipment is dominantly related to low precision.Because of the reliable,safe and easy-to-operate technology provided by deep learning-based video surveillance for unmanned inspection of electrical equipment,this paper uses the bottleneck attention module(BAM)attention mechanism to improve the Solov2 model and proposes a new electrical equipment segmentation mode.Firstly,the BAM attention mechanism is integrated into the feature extraction network to adaptively learn the correlation between feature channels,thereby improving the expression ability of the feature map;secondly,the weighted sum of CrossEntropy Loss and Dice loss is designed as the mask loss to improve the segmentation accuracy and robustness of the model;finally,the non-maximal suppression(NMS)algorithm to better handle the overlap problem in instance segmentation.Experimental results show that the proposed method achieves an average segmentation accuracy of mAP of 80.4% on three types of electrical equipment datasets,including transformers,insulators and voltage transformers,which improve the detection accuracy by more than 5.7% compared with the original Solov2 model.The segmentation model proposed can provide a focusing technical means for the intelligent management of power systems. 展开更多
关键词 Deep learning electrical equipment attention mechanism weighted loss function
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Brain networks in newborns and infants with and without sensorineural hearing loss:A functional near-infrared spectroscopy study
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作者 Juan Tan Qian-Mei Hou +4 位作者 Fen Zhang Xu Duan Yan-Long Zhang Yu-Jun Lee Hao Yan 《World Journal of Psychiatry》 SCIE 2024年第10期1547-1557,共11页
BACKGROUND Understanding the impact of early sensory deficits on brain development is essential for understanding developmental processes and developing potential interventions.While previous studies have looked into ... BACKGROUND Understanding the impact of early sensory deficits on brain development is essential for understanding developmental processes and developing potential interventions.While previous studies have looked into the impact of prenatal experiences on language development,there is a lack of research on how these experiences affect early language and brain function development in individuals with sensorineural hearing loss(SNHL).AIM To investigate SNHL effects on early brain development and connectivity in 4-month-olds vs healthy newborns and controls.METHODS The research involved analyzing the functional brain networks of 65 infants,categorized into three groups:28 healthy newborns,224-month-old participants with SNHL,and 15 age-matched healthy participants.The resting-state functional connectivity was measured and compared between the groups using functional near-infrared spectroscopy and graph theory to assess the brain network properties.RESULTS Significant differences were found in resting-state functional connectivity between participants with SNHL and age-matched controls,indicating a developmental lag in brain connectivity for those with SNHL.Surprisingly,SNHL participants showed better connectivity development compared to healthy newborns,with connectivity strengths of 0.13±0.04 for SNHL,0.16±0.08 for controls,and 0.098±0.04 for newborns.Graph theory analysis revealed enhanced global brain network properties for the SNHL group,suggesting higher communication efficiency at 4 months.No significant differences were noted in network properties between 4-month-old SNHL participants and neonates.A unique pattern of central hubs was observed in the SNHL group,with 2 hubs in the left hemisphere compared to 6 in controls.CONCLUSION 4-month-old infants with SNHL have a distinct brain network pattern with efficient long-distance information transmission but less effective local communication compared to age-matched controls. 展开更多
关键词 Early brain development Sensory hearing loss Language development Graph theory functional connectivity
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Sound Transmission Loss Analysis of a Double Plate-Acoustic Cavity Coupling System with In-Plane Functionally Graded Materials
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作者 Changzhong Chen Mingfei Chen Wenliang Yu 《Journal of Applied Mathematics and Physics》 2024年第6期2333-2345,共13页
In this paper, the isogeometric analysis (IGA) is employed to develop an acoustic radiation model for a double plate-acoustic cavity coupling system, with a focus on analyzing the sound transmission loss (STL). The fu... In this paper, the isogeometric analysis (IGA) is employed to develop an acoustic radiation model for a double plate-acoustic cavity coupling system, with a focus on analyzing the sound transmission loss (STL). The functionally graded (FG) plate exhibits a different material properties in-plane, and the power-law rule is adopted as the governing principle for material mixing. To validate the harmonic response and demonstrate the accuracy and convergence of the isogeometric modeling, ANASYS is utilized to compare with numerical examples. A plane wave serves as the acoustic excitation, and the Rayleigh integral is applied to discretize the radiated plate. The STL results are compared with the literature, confirming the reliability of the coupling system. Finally, the investigation is conducted to study impact of cavity depth and power-law parameter on the STL. 展开更多
关键词 Isogeometric Analysis Sound Transmission loss Double-Plate System functionally Graded Materials Acoustic Structure Coupling
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Loss Aware Feature Attention Mechanism for Class and Feature Imbalance Issue
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作者 Yuewei Wu Ruiling Fu +1 位作者 Tongtong Xing Fulian Yin 《Computers, Materials & Continua》 SCIE EI 2025年第1期751-775,共25页
In the Internet era,recommendation systems play a crucial role in helping users find relevant information from large datasets.Class imbalance is known to severely affect data quality,and therefore reduce the performan... In the Internet era,recommendation systems play a crucial role in helping users find relevant information from large datasets.Class imbalance is known to severely affect data quality,and therefore reduce the performance of recommendation systems.Due to the imbalance,machine learning algorithms tend to classify inputs into the positive(majority)class every time to achieve high prediction accuracy.Imbalance can be categorized such as by features and classes,but most studies consider only class imbalance.In this paper,we propose a recommendation system that can integrate multiple networks to adapt to a large number of imbalanced features and can deal with highly skewed and imbalanced datasets through a loss function.We propose a loss aware feature attention mechanism(LAFAM)to solve the issue of feature imbalance.The network incorporates an attention mechanism and uses multiple sub-networks to classify and learn features.For better results,the network can learn the weights of sub-networks and assign higher weights to important features.We propose suppression loss to address class imbalance,which favors negative loss by penalizing positive loss,and pays more attention to sample points near the decision boundary.Experiments on two large-scale datasets verify that the performance of the proposed system is greatly improved compared to baseline methods. 展开更多
关键词 Imbalanced data deep learning e-commerce recommendation loss function big data analysis
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Maxillofacial Prosthesis for Partial Edentulism with Maxillary Bone Loss
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作者 Hassan El Alaoui El Abidi Fatima Zahra Ghazzar Samira Bellemkhannate 《Health》 2025年第1期13-22,共10页
Maxillary bone loss impairs essential functions (chewing, swallowing, speech) and gives patients a very unaesthetic appearance due to the removal of facial support tissues, leading to serious psychological consequence... Maxillary bone loss impairs essential functions (chewing, swallowing, speech) and gives patients a very unaesthetic appearance due to the removal of facial support tissues, leading to serious psychological consequences. Treatment is multidisciplinary and requires a resective surgery if the cause is tumor-related, or an additive surgery if the cause is traumatic. This article aims to show the role of making a prosthesis to restore function (chewing, swallowing, speech) and aesthetics following maxillary bone loss. We will eighter present a clinical case involving a right maxillary tumor that was surgically resected followed by radiotherapy, and subsequently rehabilitated with a maxillofacial prosthesis in the consultation and dental treatment center of the university hospital center of Casablanca. 展开更多
关键词 TUMOR Maxillary Bone loss Maxillofacial Prosthesis AESTHETICS function Quality of Life
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Artificial hearing systems based on functional cochlea models
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作者 Jinke Chang Sita Tarini Clark +3 位作者 Iwan Roberts Filip Hrncirik Zhipeng Zhang Manohar Bance 《International Journal of Extreme Manufacturing》 2025年第1期73-94,共22页
The cochlea is one of the most complex organs in the human body,exhibiting a complex interplay of characteristics in acoustic,mechanical,electrical,and biological functions.Functional cochlea models are an essential p... The cochlea is one of the most complex organs in the human body,exhibiting a complex interplay of characteristics in acoustic,mechanical,electrical,and biological functions.Functional cochlea models are an essential platform for studying hearing mechanics and are crucial for developing next-generation auditory prostheses and artificial hearing systems for sensorineural hearing restoration.Recent advances in additive manufacturing,organ-on-a-chip models,drug delivery platforms,and artificial intelligence have provided valuable insights into how to manufacture artificial cochlea models that more accurately replicate the complex anatomy and physiology of the inner ear.This paper reviews recent advancements in the applications of advanced manufacturing techniques in reproducing the physical,biological,and intelligent functions of the cochlea.It also outlines the current challenges to developing mechanically,electrically,and anatomically accurate functional models of the inner ear.Finally,this review identifies the major requirements and outlook for impactful research in this field going forward.Through interdisciplinary collaboration and innovation,these functional cochlea models are poised to drive significant advancements in hearing treatments,and ultimately enhance the quality of life for individuals with hearing loss. 展开更多
关键词 functional cochlea model auditory system hearing loss advanced manufacturing artificial hearing
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Effects of Normalised SSIM Loss on Super-Resolution Tasks
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作者 Adéla Hamplová TomášNovák +1 位作者 MiroslavŽácek JiríBrožek 《Computer Modeling in Engineering & Sciences》 2025年第6期3329-3349,共21页
This study proposes a new component of the composite loss function minimised during training of the Super-Resolution(SR)algorithms—the normalised structural similarity index loss LSSIMN,which has the potential to imp... This study proposes a new component of the composite loss function minimised during training of the Super-Resolution(SR)algorithms—the normalised structural similarity index loss LSSIMN,which has the potential to improve the natural appearance of reconstructed images.Deep learning-based super-resolution(SR)algorithms reconstruct high-resolution images from low-resolution inputs,offering a practical means to enhance image quality without requiring superior imaging hardware,which is particularly important in medical applications where diagnostic accuracy is critical.Although recent SR methods employing convolutional and generative adversarial networks achieve high pixel fidelity,visual artefacts may persist,making the design of the loss function during training essential for ensuring reliable and naturalistic image reconstruction.Our research shows on two models—SR and Invertible Rescaling Neural Network(IRN)—trained on multiple benchmark datasets that the function LSSIMN significantly contributes to the visual quality,preserving the structural fidelity on the reference datasets.The quantitative analysis of results while incorporating LSSIMN shows that including this loss function component has a mean 2.88%impact on the improvement of the final structural similarity of the reconstructed images in the validation set,in comparison to leaving it out and 0.218%in comparison when this component is non-normalised. 展开更多
关键词 SUPER-RESOLUTION convolutional neural networks composite loss function structural similarity normalisation training optimisation
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A suitable organic fertilizer substitution ratio stabilizes rainfed maize yields and reduces gaseous nitrogen loss in the Loess Plateau, China
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作者 Lihua Xie Lingling Li +4 位作者 Junhong Xie Jinbin Wang Zechariah Effah Setor Kwami Fudjoe Muhammad Zahid Mumtaz 《Journal of Integrative Agriculture》 2025年第6期2138-2154,共17页
The application of organic fertilizers has become an increasingly popular practice in maize production to reduce thegaseous nitrogen(N) loss and soil degradation caused by inorganic fertilizers. Organic fertilizer pla... The application of organic fertilizers has become an increasingly popular practice in maize production to reduce thegaseous nitrogen(N) loss and soil degradation caused by inorganic fertilizers. Organic fertilizer plays a key rolein improving soil quality and stabilizing maize yields, but few studies have compared different substitution rates. Afield study was carried out in 2021 and 2022, based on a long-term trial initiated in 2016, which included five organicfertilizer N substitution rates with equal inputs of 200 kg N ha^(–1): 0% organic fertilizer(T1, 100% inorganic fertilizer),50.0% organic+50.0% inorganic fertilizer(T2), 37.5% organic+62.5% inorganic fertilizer(T3), 25.0% organic+75.0%inorganic fertilizer(T4), and 12.5% organic+87.5% inorganic fertilizer(T5), as well as a no fertilizer control(T6). Theresults of the two years showed that T3 and T1 had the highest grain yield and biomass, respectively, and there wasno significant difference between T1 and T3. Compared with T1, the 12.5, 25.0, 37.5, and 50.0% substitution rates in T5, T4, T3, and T2 significantly reduced total nitrogen losses(NH_(3), N_(2)O) by 8.3, 16.1, 18.7, and 27.0%, respectively.Nitrogen use efficiency(NUE) was higher in T5, T3, and T1, and there were no significant differences among them.Organic fertilizer substitution directly reduced NH_(3)volatilization and N_(2)O emission from farmland by lowering theammonium nitrogen and alkali-dissolved N contents and by increasing soil moisture. These substitution treatmentsreduced N_(2)O emissions indirectly by regulating the abundances of AOB and nirK-harboring genes by promotingsoil moisture. Specifically, the 37.5% organic fertilizer substitution reduces NH_(3)volatilization and N_(2)O emission from farmland by reducing the ammonium nitrogen and alkali-dissolved N contents and increasing moisture, which negatively regulate the abundance of AOB and nir K-harboring genes to reduce N_(2)O emissions indirectly in rainfed maize fields on the Loess Plateau of China. 展开更多
关键词 organic fertilizer rainfed maize field gaseous nitrogen loss functional gene
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Convolutional Graph Neural Network with Novel Loss Strategies for Daily Temperature and Precipitation Statistical Downscaling over South China
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作者 Wenjie YAN Shengjun LIU +6 位作者 Yulin ZOU Xinru LIU Diyao WEN Yamin HU Dangfu YANG Jiehong XIE Liang ZHAO 《Advances in Atmospheric Sciences》 2025年第1期232-247,共16页
Traditional meteorological downscaling methods face limitations due to the complex distribution of meteorological variables,which can lead to unstable forecasting results,especially in extreme scenarios.To overcome th... Traditional meteorological downscaling methods face limitations due to the complex distribution of meteorological variables,which can lead to unstable forecasting results,especially in extreme scenarios.To overcome this issue,we propose a convolutional graph neural network(CGNN)model,which we enhance with multilayer feature fusion and a squeeze-and-excitation block.Additionally,we introduce a spatially balanced mean squared error(SBMSE)loss function to address the imbalanced distribution and spatial variability of meteorological variables.The CGNN is capable of extracting essential spatial features and aggregating them from a global perspective,thereby improving the accuracy of prediction and enhancing the model's generalization ability.Based on the experimental results,CGNN has certain advantages in terms of bias distribution,exhibiting a smaller variance.When it comes to precipitation,both UNet and AE also demonstrate relatively small biases.As for temperature,AE and CNNdense perform outstandingly during the winter.The time correlation coefficients show an improvement of at least 10%at daily and monthly scales for both temperature and precipitation.Furthermore,the SBMSE loss function displays an advantage over existing loss functions in predicting the98th percentile and identifying areas where extreme events occur.However,the SBMSE tends to overestimate the distribution of extreme precipitation,which may be due to the theoretical assumptions about the posterior distribution of data that partially limit the effectiveness of the loss function.In future work,we will further optimize the SBMSE to improve prediction accuracy. 展开更多
关键词 statistical downscaling convolutional graph neural network feature processing SBMSE loss function
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LR-Net:Lossless Feature Fusion and Revised SIoU for Small Object Detection
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作者 Gang Li Ru Wang +5 位作者 Yang Zhang Chuanyun Xu Xinyu Fan Zheng Zhou Pengfei Lv Zihan Ruan 《Computers, Materials & Continua》 2025年第11期3267-3288,共22页
Currently,challenges such as small object size and occlusion lead to a lack of accuracy and robustness in small object detection.Since small objects occupy only a few pixels in an image,the extracted features are limi... Currently,challenges such as small object size and occlusion lead to a lack of accuracy and robustness in small object detection.Since small objects occupy only a few pixels in an image,the extracted features are limited,and mainstream downsampling convolution operations further exacerbate feature loss.Additionally,due to the occlusionprone nature of small objects and their higher sensitivity to localization deviations,conventional Intersection over Union(IoU)loss functions struggle to achieve stable convergence.To address these limitations,LR-Net is proposed for small object detection.Specifically,the proposed Lossless Feature Fusion(LFF)method transfers spatial features into the channel domain while leveraging a hybrid attentionmechanism to focus on critical features,mitigating feature loss caused by downsampling.Furthermore,RSIoU is proposed to enhance the convergence performance of IoU-based losses for small objects.RSIoU corrects the inherent convergence direction issues in SIoU and proposes a penalty term as a Dynamic Focusing Mechanism parameter,enabling it to dynamically emphasize the loss contribution of small object samples.Ultimately,RSIoU significantly improves the convergence performance of the loss function for small objects,particularly under occlusion scenarios.Experiments demonstrate that LR-Net achieves significant improvements across variousmetrics onmultiple datasets compared with YOLOv8n,achieving a 3.7% increase in mean Average Precision(AP)on the VisDrone2019 dataset,along with improvements of 3.3% on the AI-TOD dataset and 1.2% on the COCO dataset. 展开更多
关键词 Small object detection lossless feature fusion attention mechanisms loss function penalty term
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Beneficial effects of antidepressant mirtazapine in functional dyspepsia patients with weight loss 被引量:20
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作者 Shu-Man Jiang Lin Jia +2 位作者 Jing Liu Man-Man Shi Ming-Zhi Xu 《World Journal of Gastroenterology》 SCIE CAS 2016年第22期5260-5266,共7页
AIM: To explore the effects and mechanism of action of antidepressant mirtazapine in functional dyspepsia(FD) patients with weight loss.METHODS: Sixty depressive FD patients with weight loss were randomly divided into... AIM: To explore the effects and mechanism of action of antidepressant mirtazapine in functional dyspepsia(FD) patients with weight loss.METHODS: Sixty depressive FD patients with weight loss were randomly divided into a mirtazapine group(MG), a paroxetine group(PG) or a conventional therapy group(CG) for an 8-wk clinical trial. Adverse effects and treatment response were recorded. The Nepean Dyspepsia Index-symptom(NDSI) checklist and the 17-item Hamilton Rating Scale of Depression(HAMD-17) were used to evaluate dyspepsia and depressive symptoms, respectively. The body composition analyzer was used to measure body weight and fat. Serum hormone levels were measured by ELISA.RESULTS:(1) After 2 wk of treatment, NDSI scores were significantly lower for the MG than for the PG and CG;(2) After 4 or 8 wk of treatment, HAMD-17 scores were significantly lower for the MG and PG than for the CG;(3) After 8 wk of treatment, patients in the MG experienced a weight gain of 3.58 ± 1.57 kg, which was significantly higher than that observed for patients in the PG and CG. Body fat increased by 2.77 ± 0.14kg, the body fat ratio rose by 4%, and the visceral fat area increased by 7.56 ± 2.25 cm2; and(4) For the MG, serum hormone levels of ghrelin, neuropeptide Y(NPY), motilin(MTL) and gastrin(GAS) were significantly upregulated; in contrast, those of leptin, 5-hydroxytryptamine(5-HT) and cholecystokinin(CCK) were significantly downregulated. CONCLUSION: Mirtazapine not only alleviates symptoms associated with dyspepsia and depression linked to FD in patients with weight loss but also significantly increases body weight(mainly the visceral fat in body fat). The likely mechanism of mirtazapine action is regulation of brain-gut or gastrointestinal hormone levels. 展开更多
关键词 Mirtazapine functionAL DYSPEPSIA WEIGHT loss DEPRESSION
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The Credibility Models under LINEX Loss Functions 被引量:8
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作者 WEN Li-min ZHANG Xiankun ZHENG Dan FANG .ling 《Chinese Quarterly Journal of Mathematics》 CSCD 2012年第3期397-402,共6页
LINEX(linear and exponential) loss function is a useful asymmetric loss function. The purpose of using a LINEX loss function in credibility models is to solve the problem of very high premium by suing a symmetric quad... LINEX(linear and exponential) loss function is a useful asymmetric loss function. The purpose of using a LINEX loss function in credibility models is to solve the problem of very high premium by suing a symmetric quadratic loss function in most of classical credibility models. The Bayes premium and the credibility premium are derived under LINEX loss function. The consistency of Bayes premium and credibility premium were also checked. Finally, the simulation was introduced to show the differences between the credibility estimator we derived and the classical one. 展开更多
关键词 LINEX loss function credibility estimator Bayes premium
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Vibration and sound transmission loss characteristics of porous foam functionally graded sandwich panels in thermal environment 被引量:3
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作者 Wenhao YUAN Haitao LIAO +1 位作者 Ruxin GAO Fenglian LI 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第6期897-916,共20页
This study investigates the vibration and acoustic properties of porous foam functionally graded(FG)plates under the influence of the temperature field.The dynamics equations of the system are established based on Ham... This study investigates the vibration and acoustic properties of porous foam functionally graded(FG)plates under the influence of the temperature field.The dynamics equations of the system are established based on Hamilton's principle by using the higher-order shear deformation theory under the linear displacement-strain assumption.The displacement shape function is assumed according to the four-sided simply-supported(SSSS)boundary condition,and the characteristic equations of the system are derived by combining the motion control equations.The theoretical model of vibro-acoustic coupling is established by using the acoustic theory and fluid-structure coupling solution method under the simple harmonic acoustic wave.The system's natural frequency and sound transmission loss(STL)are obtained through programming calculations and compared with the literature and COMSOL simulation to verify the validity and reliability of the theoretical model.The effects of various factors,such as temperature,porosity coefficients,gradient index,core thickness,width-to-thickness ratio on the vibration,and STL characteristics of the system,are discussed.The results provide a theoretical basis for the application of porous foam FG plates in engineering to optimize vibration and sound transmission properties. 展开更多
关键词 porous foam functionally graded(FG)plate thermal environment natural frequency sound transmission loss(STL)
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Application of Weighted Cross-Entropy Loss Function in Intrusion Detection 被引量:3
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作者 Ziyun Zhou Hong Huang Binhao Fang 《Journal of Computer and Communications》 2021年第11期1-21,共21页
The deep learning model is overfitted and the accuracy of the test set is reduced when the deep learning model is trained in the network intrusion detection parameters, due to the traditional loss function convergence... The deep learning model is overfitted and the accuracy of the test set is reduced when the deep learning model is trained in the network intrusion detection parameters, due to the traditional loss function convergence problem. Firstly, we utilize a network model architecture combining Gelu activation function and deep neural network;Secondly, the cross-entropy loss function is improved to a weighted cross entropy loss function, and at last it is applied to intrusion detection to improve the accuracy of intrusion detection. In order to compare the effect of the experiment, the KDDcup99 data set, which is commonly used in intrusion detection, is selected as the experimental data and use accuracy, precision, recall and F1-score as evaluation parameters. The experimental results show that the model using the weighted cross-entropy loss function combined with the Gelu activation function under the deep neural network architecture improves the evaluation parameters by about 2% compared with the ordinary cross-entropy loss function model. Experiments prove that the weighted cross-entropy loss function can enhance the model’s ability to discriminate samples. 展开更多
关键词 Cross-Entropy loss function Visualization Analysis Intrusion Detection KDD Data Set ACCURACY
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Evolution and Effectiveness of Loss Functions in Generative Adversarial Networks 被引量:1
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作者 Ali Syed Saqlain Fang Fang +2 位作者 Tanvir Ahmad Liyun Wang Zain-ul Abidin 《China Communications》 SCIE CSCD 2021年第10期45-76,共32页
Recently,the evolution of Generative Adversarial Networks(GANs)has embarked on a journey of revolutionizing the field of artificial and computational intelligence.To improve the generating ability of GANs,various loss... Recently,the evolution of Generative Adversarial Networks(GANs)has embarked on a journey of revolutionizing the field of artificial and computational intelligence.To improve the generating ability of GANs,various loss functions are introduced to measure the degree of similarity between the samples generated by the generator and the real data samples,and the effectiveness of the loss functions in improving the generating ability of GANs.In this paper,we present a detailed survey for the loss functions used in GANs,and provide a critical analysis on the pros and cons of these loss functions.First,the basic theory of GANs along with the training mechanism are introduced.Then,the most commonly used loss functions in GANs are introduced and analyzed.Third,the experimental analyses and comparison of these loss functions are presented in different GAN architectures.Finally,several suggestions on choosing suitable loss functions for image synthesis tasks are given. 展开更多
关键词 loss functions deep learning machine learning unsupervised learning generative adversarial networks(GANs) image synthesis
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Path Loss Modeling: A Machine Learning Based Approach Using Support Vector Regression and Radial Basis Function Models 被引量:3
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作者 Stephen Ojo Arif Sari Taiwo P. Ojo 《Open Journal of Applied Sciences》 2022年第6期990-1010,共21页
Path loss prediction models are vital for accurate signal propagation in wireless channels. Empirical and deterministic models used in path loss predictions have not produced optimal results. In this paper, we introdu... Path loss prediction models are vital for accurate signal propagation in wireless channels. Empirical and deterministic models used in path loss predictions have not produced optimal results. In this paper, we introduced machine learning algorithms to path loss predictions because it offers a flexible network architecture and extensive data can be used. We introduced support vector regression (SVR) and radial basis function (RBF) models to path loss predictions in the investigated environments. The SVR model was able to process several input parameters without introducing complexity to the network architecture. The RBF on its part provides a good function approximation. Hyperparameter tuning of the machine learning models was carried out in order to achieve optimal results. The performances of the SVR and RBF models were compared and result validated using the root-mean squared error (RMSE). The two machine learning algorithms were also compared with the Cost-231, SUI, Egli, Freespace, Cost-231 W-I models. The analytical models overpredicted path loss. Overall, the machine learning models predicted path loss with greater accuracy than the empirical models. The SVR model performed best across all the indices with RMSE values of 1.378 dB, 1.4523 dB, 2.1568 dB in rural, suburban and urban settings respectively and should therefore be adopted for signal propagation in the investigated environments and beyond. 展开更多
关键词 Support Vector Regression Radial Basis function Machine Learning Path loss Empirical DETERMINISTIC
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基于Focal-EIOU函数的被动式太赫兹图像违禁物品识别 被引量:10
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作者 周敏 《太赫兹科学与电子信息学报》 2022年第8期810-816,共7页
针对被动式太赫兹安检系统因环境影响导致图像质量波动,从而影响识别算法,导致准确率大幅降低的问题,提出了基于Focal-EIOU损失函数的改进YOLOv4算法,并用被动式太赫兹人体安检图像对刀、枪违禁物品进行模型训练获得模型。建立不同环境... 针对被动式太赫兹安检系统因环境影响导致图像质量波动,从而影响识别算法,导致准确率大幅降低的问题,提出了基于Focal-EIOU损失函数的改进YOLOv4算法,并用被动式太赫兹人体安检图像对刀、枪违禁物品进行模型训练获得模型。建立不同环境、不同位置角度携带刀枪嫌疑物人员的太赫兹图像数据库,采用图像增广的方法构建丰富数据集;将YOLOv4的CIOU loss改进为Focal-EIOU loss,提高算法对太赫兹图像识别的鲁棒性,进而经过训练获得较优的模型。在本文的测试集中,使用改进后的算法训练的模型平均检测精确度(mAP)达到96.4%,检测速度在28 ms左右,交并比(IOU)平均值为0.95,在同等条件下高于常规算法,改善了检测识别的效果。实验结果表明,本文方法能够有效提高被动式太赫兹人体安检系统的嫌疑物识别准确率,有利于该项技术在人体安检领域的推广应用。 展开更多
关键词 太赫兹成像 人体安检 目标识别 损失函数
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Effect of foot reflexology on an infant with sensorineural hearing loss:A case report 被引量:6
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作者 Yu-Jun Lee Mao-Qing Chen Jie Dong 《World Journal of Clinical Cases》 SCIE 2024年第8期1437-1441,共5页
BACKGROUND Our study contributes to the further understanding of the mechanism of foot reflexology.Foot reflexology has been reported to affect hearing recovery,but no physiological evidence has been provided.This lac... BACKGROUND Our study contributes to the further understanding of the mechanism of foot reflexology.Foot reflexology has been reported to affect hearing recovery,but no physiological evidence has been provided.This lack of evidence hampers the acceptance of the technique in clinical practice.CASE SUMMARY A girl was taken to North Sichuan Medical University Affiliated Hospital for a hearing screen by her parents.Her parents reported that her hearing level was the same as when she was born.The girl was diagnosed with sensorineural hearing loss(SNHL)by a doctor in the otolaryngology department.After we introduced the foot reflexology project,the parents agreed to participate in the experiment.After 6 months of foot reflexology treatment,the hearing threshold of the girl recovered to a normal level,below 30 dB.CONCLUSION Foot reflexology should be encouraged in clinical practice and for families of infants with SNHL. 展开更多
关键词 Infant with sensorineural hearing loss Foot reflexology functional connectivity Language development Case report
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