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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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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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基于改进型Softmax Loss损失函数的面部表情识别
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作者 李校林 张鹏飞 +1 位作者 董玉晖 钮海涛 《计算机仿真》 北大核心 2023年第5期234-238,256,共6页
针对面部表情识别中Softmax Loss损失函数类内特征分散、类间特征未分离的问题,提出一种改进型Softmax Loss损失函数ACAM Loss。上述损失函数将优化集中在余弦角度上,在特征与目标权重的余弦夹角加上间隔m,在特征与非目标权重的余弦夹... 针对面部表情识别中Softmax Loss损失函数类内特征分散、类间特征未分离的问题,提出一种改进型Softmax Loss损失函数ACAM Loss。上述损失函数将优化集中在余弦角度上,在特征与目标权重的余弦夹角加上间隔m,在特征与非目标权重的余弦夹角减去间隔m,有效引导网络学习具备类内距离较小、类间距离较大的强区分度特征,同时加大网络训练力度优化输出,以提升分类效果。实验表明,在CK+和JAFFE数据集上,ACAM Loss函数训练模型表情识别准确率分别达到98.87%和98.92%,相比Softmax Loss函数平均增幅分别为1.35%和1.3%,识别准确率处于主流领先水平,验证了改进损失函数的有效性。 展开更多
关键词 面部表情识别 分类 损失函数 加性余弦角度间隔
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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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Application of Weighted Cross-Entropy Loss Function in Intrusion Detection 被引量:2
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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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Beneficial effects of antidepressant mirtazapine in functional dyspepsia patients with weight loss 被引量:19
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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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Economic Design of & S Control Charts Based on Taguchi's Loss Function and Its Optimization
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作者 GUO Yu YANG Wen'an +1 位作者 LIAO Wenhe GAO Shiwen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2012年第3期576-586,共11页
Much research effort has been devoted to economic design of X & S control charts,however,there are some problems in usual methods.On the one hand,it is difficult to estimate the relationship between costs and other m... Much research effort has been devoted to economic design of X & S control charts,however,there are some problems in usual methods.On the one hand,it is difficult to estimate the relationship between costs and other model parameters,so the economic design method is often not effective in producing charts that can quickly detect small shifts before substantial losses occur;on the other hand,in many cases,only one type of process shift or only one pair of process shifts are taken into consideration,which may not correctly reflect the actual process conditions.To improve the behavior of economic design of control chart,a cost & loss model with Taguchi's loss function for the economic design of X & S control charts is embellished,which is regarded as an optimization problem with multiple statistical constraints.The optimization design is also carried out based on a number of combinations of process shifts collected from the field operation of the conventional control charts,thus more hidden information about the shift combinations is mined and employed to the optimization design of control charts.At the same time,an improved particle swarm optimization(IPSO) is developed to solve such an optimization problem in design of X & S control charts,IPSO is first tested for several benchmark problems from the literature and evaluated with standard performance metrics.Experimental results show that the proposed algorithm has significant advantages on obtaining the optimal design parameters of the charts.The proposed method can substantially reduce the total cost(or loss) of the control charts,and it will be a promising tool for economic design of control charts. 展开更多
关键词 statistical process control control charts Taguchi's loss function OPTIMIZATION particle swarm optimization
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ENERGY-LOSS FUNCTIONS DERIVED FROM REELS SPECTRA FOR ALUMINUM
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作者 Z.M.Zhang Z.J.Ding +5 位作者 H.M.Li K.Salma X.Sun R.Shimizu T.Koshikawa K.Goto 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2005年第3期217-222,共6页
The effective energy loss functions for Al have been derived from differential i nverse inelastic mean free path based on the extended Landau approach. It has be en revealed that the effective energy loss function is ... The effective energy loss functions for Al have been derived from differential i nverse inelastic mean free path based on the extended Landau approach. It has be en revealed that the effective energy loss function is very close in value to th e theoretical surface energy loss function in the lower energy loss region but g radually approaches the theoretical bulk energy loss function in the higher ener gy loss region. Moreover, the intensity corresponding to surface excitation in e ffective energy loss functions decreases with the increase of primary electron e nergy. These facts show that the present effective energy loss function describe s not only surface excitation but also bulk excitation. At last, REELS spectra s imulated by Monte Carlo method based on use of the effective energy loss functio ns has reproduced the experimental REELS spectra with considerable success. 展开更多
关键词 effective energy loss function Monte Carlo simulation extended Landau approach reflection electron energy loss spectro scopy ALUMINUM
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ANALYSIS TO NEYMAN-PEARSON CLASSIFICATION WITH CONVEX LOSS FUNCTION
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作者 Min Han Dirong Chen Zhaoxu Sun 《Analysis in Theory and Applications》 2008年第1期18-28,共11页
Neyman-Pearson classification has been studied in several articles before. But they all proceeded in the classes of indicator functions with indicator function as the loss function, which make the calculation to be di... Neyman-Pearson classification has been studied in several articles before. But they all proceeded in the classes of indicator functions with indicator function as the loss function, which make the calculation to be difficult. This paper investigates Neyman- Pearson classification with convex loss function in the arbitrary class of real measurable functions. A general condition is given under which Neyman-Pearson classification with convex loss function has the same classifier as that with indicator loss function. We give analysis to NP-ERM with convex loss function and prove it's performance guarantees. An example of complexity penalty pair about convex loss function risk in terms of Rademacher averages is studied, which produces a tight PAC bound of the NP-ERM with convex loss function. 展开更多
关键词 Neyman-Pearson lemma convex loss function Neyman-Pearson classifica-tion NP-ERM Rademacher average
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Evolution and Effectiveness of Loss Functions in Generative Adversarial Networks
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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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Calculations of Energy-Loss Function for 26 Materials
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作者 Yang Sun Huan Xu +2 位作者 Bo Da Shi-feng Mao Ze-jun Ding 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2016年第6期663-670,I0001,共9页
我们为 26 体积材料的精力损失功能的现在的适合计算,包括 18 个纯元素( Ag ,艾尔, Au , C ,公司, C , Cu ,嗯, Fe , Ge , Mg ,瞬间, Nb , Ni , Pd ,磅, Si , Te )并且 8 混合物( AgCl ,艾尔 <sub>2</sub &... 我们为 26 体积材料的精力损失功能的现在的适合计算,包括 18 个纯元素( Ag ,艾尔, Au , C ,公司, C , Cu ,嗯, Fe , Ge , Mg ,瞬间, Nb , Ni , Pd ,磅, Si , Te )并且 8 混合物( AgCl ,艾尔 <sub>2</sub > O <sub>3</sub>,哎呀, CdS , SiO <sub>2</sub>, ZnS , ZnSe , ZnTe )申请出现电子光谱学分析。试验性的精力损失功能,从测量光数据被导出,基于 Drude-Lindhard 绝缘的模型被适合进公式的有限的和。由检查振荡器力量和和 perfect-screening-sum 规则,我们验证了恰当的结果的高精确性。基于适合的参数,而且,模仿的思考电子精力损失光谱学(卷) 光谱与实验显示出一个好协议。精力损失功能的计算适合参数在 http://micro.ustc.edu.cn/ELF/ELF.html 在一个开、联机的数据库被存储。 展开更多
关键词 电子能量损失谱 拟合计算 损失函数 AL2O3 材料 电子能谱分析 AGCL SIO2
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CONTINUOUS-TIME STOCHASTIC ADAPTIVE CONTROL STABILIZING THE SYSTEM AND MINIMIZING THE QUADRATIC LOSS FUNCTION
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作者 CHEN Hanfu(Institute of Systems Science, Academia Sinica, Beijing 100080 China) 《Systems Science and Mathematical Sciences》 SCIE EI CSCD 1995年第2期166-181,共16页
CONTINUOUS-TIMESTOCHASTICADAPTIVECONTROLSTABILIZINGTHESYSTEMANDMINIMIZINGTHEQUADRATICLOSSFUNCTIONCHENHanfu(I... CONTINUOUS-TIMESTOCHASTICADAPTIVECONTROLSTABILIZINGTHESYSTEMANDMINIMIZINGTHEQUADRATICLOSSFUNCTIONCHENHanfu(InstituteofSystems... 展开更多
关键词 STOCHASTIC ADAPTIVE control CONTINUOUS-TIME systems consistent estimate QUADRATIC loss function
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The Credibility Estimators under MLINEX Loss Function
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作者 ZHANG Qiang CUI Qian-qian CHEN Ping 《Chinese Quarterly Journal of Mathematics》 2018年第1期43-50,共8页
In this paper, MLINEX loss function was considered to solve the problem of high premium in credibility models. The Bayes premium and credibility premium were obtained under MLINEX loss function by using a symmetric qu... In this paper, MLINEX loss function was considered to solve the problem of high premium in credibility models. The Bayes premium and credibility premium were obtained under MLINEX loss function by using a symmetric quadratic loss function. A credibility model with multiple contracts was established and the corresponding credibility estimator was derived under MLINEX loss function. For this model the estimations of the structure parameters and a numerical example were also given. 展开更多
关键词 损失 评估 结构参数 模型 个数
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Survey on the Loss Function of Deep Learning in Face Recognition
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作者 Jun Wang Suncheng Feng +1 位作者 Yong Cheng Najla Al-Nabhan 《Journal of Information Hiding and Privacy Protection》 2021年第1期29-45,共17页
With the continuous development of face recognition network,the selection of loss function plays an increasingly important role in improving accuracy.The loss function of face recognition network needs to minimize the... With the continuous development of face recognition network,the selection of loss function plays an increasingly important role in improving accuracy.The loss function of face recognition network needs to minimize the intra-class distance while expanding the inter-class distance.So far,one of our mainstream loss function optimization methods is to add penalty terms,such as orthogonal loss,to further constrain the original loss function.The other is to optimize using the loss based on angular/cosine margin.The last is Triplet loss and a new type of joint optimization based on HST Loss and ACT Loss.In this paper,based on the three methods with good practical performance and the joint optimization method,various loss functions are thoroughly reviewed. 展开更多
关键词 loss function face recognition orthogonality loss ArcFace the joint loss
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Remote Sensing Plateau Forest Segmentation with Boundary Preserving Double Loss Function Collaborative Learning
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作者 Ying Ma Jiaqi Zhang +3 位作者 Pengyu Liu Zhihao Wei Lingfei Zhang Xiaowei Jia 《Journal of New Media》 2022年第4期165-177,共13页
Plateau forest plays an important role in the high-altitude ecosystem,and contributes to the global carbon cycle.Plateau forest monitoring request in-suit data from field investigation.With recent development of the r... Plateau forest plays an important role in the high-altitude ecosystem,and contributes to the global carbon cycle.Plateau forest monitoring request in-suit data from field investigation.With recent development of the remote sensing technic,large-scale satellite data become available for surface monitoring.Due to the various information contained in the remote sensing data,obtain accurate plateau forest segmentation from the remote sensing imagery still remain challenges.Recent developed deep learning(DL)models such as deep convolutional neural network(CNN)has been widely used in image processing tasks,and shows possibility for remote sensing segmentation.However,due to the unique characteristics and growing environment of the plateau forest,generate feature with high robustness needs to design structures with high robustness.Aiming at the problem that the existing deep learning segmentation methods are difficult to generate the accurate boundary of the plateau forest within the satellite imagery,we propose a method of using boundary feature maps for collaborative learning.There are three improvements in this article.First,design a multi input model for plateau forest segmentation,including the boundary feature map as an additional input label to increase the amount of information at the input.Second,we apply a strong boundary search algorithm to obtain boundary value,and propose a boundary value loss function.Third,improve the Unet segmentation network and combine dense block to improve the feature reuse ability and reduces the image information loss of the model during training.We then demonstrate the utility of our method by detecting plateau forest regions from ZY-3 satellite regarding to Sanjiangyuan nature reserve.The experimental results show that the proposed method can utilize multiple feature information comprehensively which is beneficial to extracting information from boundary,and the detection accuracy is generally higher than several state-of-art algorithms.As a result of this investigation,the study will contribute in several ways to our understanding of DL for region detection and will provide a basis for further researches. 展开更多
关键词 Remote sensing forest segmentation boundary preserving double loss function
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Functional Weak Laws for the Weighted Mean Losses or Gains and Applications
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作者 Gane Samb Lo Serigne Touba Sall Pape Djiby Mergane 《Applied Mathematics》 2015年第5期847-863,共17页
In this paper, we show that many risk measures arising in Actuarial Sciences, Finance, Medicine, Welfare analysis, etc. are gathered in classes of Weighted Mean Loss or Gain (WMLG) statistics. Some of them are Upper T... In this paper, we show that many risk measures arising in Actuarial Sciences, Finance, Medicine, Welfare analysis, etc. are gathered in classes of Weighted Mean Loss or Gain (WMLG) statistics. Some of them are Upper Threshold Based (UTH) or Lower Threshold Based (LTH). These statistics may be time-dependent when the scene is monitored in the time and depend on specific functions w and d. This paper provides time-dependent and uniformly functional weak asymptotic laws that allow temporal and spatial studies of the risk as well as comparison among statistics in terms of dependence and mutual influence. The results are particularized for usual statistics like the Kakwani and Shorrocks ones that are mainly used in welfare analysis. Data-driven applications based on pseudo-panel data are provided. 展开更多
关键词 Empirical PROCESS Time Dependent PROCESS WEAK Theory Risk Measures POVERTY Index loss function Economic WELFARE
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Shrinkage Testimator in Gamma Type-II Censored Data under LINEX Loss Function
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作者 Ali Shadrokh Hassan Pazira 《Open Journal of Statistics》 2013年第4期245-257,共13页
Prakash and Singh presented the shrinkage testimators under the invariant version of LINEX loss function for the scale parameter of an exponential distribution in presence Type-II censored data. In this paper, we exte... Prakash and Singh presented the shrinkage testimators under the invariant version of LINEX loss function for the scale parameter of an exponential distribution in presence Type-II censored data. In this paper, we extend this approach to gamma distribution, as Prakash and Singh’s paper is a special case of this paper. In fact, some shrinkage testimators for the scale parameter of a gamma distribution, when Type-II censored data are available, have been suggested under the LINEX loss function assuming the shape parameter is to be known. The comparisons of the proposed testimators have been made with improved estimator. All these estimators are compared empirically using Monte Carlo simulation. 展开更多
关键词 GAMMA Distribution SHRINKAGE ESTIMATOR and Factor Asymmetric loss function Level of SIGNIFICANCE Testimation Monte-Carlo Simulation
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The Effectiveness of the Squared Error and Higgins-Tsokos Loss Functions on the Bayesian Reliability Analysis of Software Failure Times under the Power Law Process
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作者 Freeh N. Alenezi Christ P. Tsokos 《Engineering(科研)》 2019年第5期272-299,共28页
Reliability analysis is the key to evaluate software’s quality. Since the early 1970s, the Power Law Process, among others, has been used to assess the rate of change of software reliability as time-varying function ... Reliability analysis is the key to evaluate software’s quality. Since the early 1970s, the Power Law Process, among others, has been used to assess the rate of change of software reliability as time-varying function by using its intensity function. The Bayesian analysis applicability to the Power Law Process is justified using real software failure times. The choice of a loss function is an important entity of the Bayesian settings. The analytical estimate of likelihood-based Bayesian reliability estimates of the Power Law Process under the squared error and Higgins-Tsokos loss functions were obtained for different prior knowledge of its key parameter. As a result of a simulation analysis and using real data, the Bayesian reliability estimate under the Higgins-Tsokos loss function not only is robust as the Bayesian reliability estimate under the squared error loss function but also performed better, where both are superior to the maximum likelihood reliability estimate. A sensitivity analysis resulted in the Bayesian estimate of the reliability function being sensitive to the prior, whether parametric or non-parametric, and to the loss function. An interactive user interface application was additionally developed using Wolfram language to compute and visualize the Bayesian and maximum likelihood estimates of the intensity and reliability functions of the Power Law Process for a given data. 展开更多
关键词 Power LAW Process BAYESIAN Reliability Intensity function KERNEL Density loss function Robustness
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Asymmetric Loss Based on Image Properties for Deep Learning-Based Image Restoration
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作者 Linlin Zhu Yu Han +5 位作者 Xiaoqi Xi Zhicun Zhang Mengnan Liu Lei Li Siyu Tan Bin Yan 《Computers, Materials & Continua》 SCIE EI 2023年第12期3367-3386,共20页
Deep learning techniques have significantly improved image restoration tasks in recent years.As a crucial compo-nent of deep learning,the loss function plays a key role in network optimization and performance enhancem... Deep learning techniques have significantly improved image restoration tasks in recent years.As a crucial compo-nent of deep learning,the loss function plays a key role in network optimization and performance enhancement.However,the currently prevalent loss functions assign equal weight to each pixel point during loss calculation,which hampers the ability to reflect the roles of different pixel points and fails to exploit the image’s characteristics fully.To address this issue,this study proposes an asymmetric loss function based on the image and data characteristics of the image recovery task.This novel loss function can adjust the weight of the reconstruction loss based on the grey value of different pixel points,thereby effectively optimizing the network training by differentially utilizing the grey information from the original image.Specifically,we calculate a weight factor for each pixel point based on its grey value and combine it with the reconstruction loss to create a new loss function.This ensures that pixel points with smaller grey values receive greater attention,improving network recovery.In order to verify the effectiveness of the proposed asymmetric loss function,we conducted experimental tests in the image super-resolution task.The experimental results show that the model with the introduction of asymmetric loss weights improves all the indexes of the processing results without increasing the training time.In the typical super-resolution network SRCNN,by introducing asymmetric weights,it is possible to improve the peak signal-to-noise ratio(PSNR)by up to about 0.5%,the structural similarity index(SSIM)by up to about 0.3%,and reduce the root-mean-square error(RMSE)by up to about 1.7%with essentially no increase in training time.In addition,we also further tested the performance of the proposed method in the denoising task to verify the potential applicability of the method in the image restoration task. 展开更多
关键词 Deep learning image restoration loss function image properties super resolution image denoising
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Seismic loss assessment of RC high-rise buildings designed according to Eurocode 8
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作者 Jelena Pejovic Nina Serdar 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第3期807-824,共18页
A probabilistic seismic loss assessment of RC high-rise(RCHR)buildings designed according to Eurocode 8 and located in the Southern Euro-Mediterranean zone is presented herein.The loss assessment methodology is based ... A probabilistic seismic loss assessment of RC high-rise(RCHR)buildings designed according to Eurocode 8 and located in the Southern Euro-Mediterranean zone is presented herein.The loss assessment methodology is based on a comprehensive simulation approach which takes into account ground motion(GM)uncertainty,and the random effects in seismic demand,as well as in predicting the damage states(DSs).The methodology is implemented on three RCHR buildings of 20-story,30-story and 40-story with a core wall structural system.The loss functions described by a cumulative lognormal probability distribution are obtained for two intensity levels for a large set of simulations(NLTHAs)based on 60 GM records with a wide range of magnitude(M),distance to source(R)and different site soil conditions(SS).The losses expressed in percent of building replacement cost for RCHR buildings are obtained.In the estimation of losses,both structural(S)and nonstructural(NS)damage for four DSs are considered.The effect of different GM characteristics(M,R and SS)on the obtained losses are investigated.Finally,the estimated performance of the RCHR buildings are checked to ensure that they fulfill limit state requirements according to Eurocode 8. 展开更多
关键词 RC high-rise buildings seismic loss assessment loss functions nonlinear time-history analysis(NLTHA) cumulative lognormal probability distribution random effects Eurocode 8
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